3 collectd.conf - Configuration for the system statistics collection daemon B<collectd>
7 BaseDir "/path/to/data/"
8 PIDFile "/path/to/pidfile/collectd.pid"
9 Server "123.123.123.123" 12345
22 This config file controls how the system statistics collection daemon
23 B<collectd> behaves. The most significant option is B<LoadPlugin>, which
24 controls which plugins to load. These plugins ultimately define collectd's
27 The syntax of this config file is similar to the config file of the famous
28 B<Apache Webserver>. Each line contains either a key-value-pair or a
29 section-start or -end. Empty lines and everything after the hash-symbol `#' is
30 ignored. Values are either string, enclosed in double-quotes,
31 (floating-point-)numbers or a boolean expression, i.E<nbsp>e. either B<true> or
32 B<false>. String containing of only alphanumeric characters and underscores do
33 not need to be quoted. Lines may be wrapped by using `\' as the last character
34 before the newline. This allows long lines to be split into multiple lines.
35 Quoted strings may be wrapped as well. However, those are treated special in
36 that whitespace at the beginning of the following lines will be ignored, which
37 allows for nicely indenting the wrapped lines.
39 The configuration is read and processed in order, i.E<nbsp>e. from top to
40 bottom. So the plugins are loaded in the order listed in this config file. It
41 is a good idea to load any logging plugins first in order to catch messages
42 from plugins during configuration. Also, the C<LoadPlugin> option B<must> occur
43 B<before> the C<E<lt>Plugin ...E<gt>> block.
49 =item B<BaseDir> I<Directory>
51 Sets the base directory. This is the directory beneath all RRD-files are
52 created. Possibly more subdirectories are created. This is also the working
53 directory for the daemon.
55 =item B<LoadPlugin> I<Plugin>
57 Loads the plugin I<Plugin>. There must be at least one such line or B<collectd>
58 will be mostly useless.
60 =item B<Include> I<Path>
62 If I<Path> points to a file, includes that file. If I<Path> points to a
63 directory, recursively includes all files within that directory and its
64 subdirectories. If the C<wordexp> function is available on your system,
65 shell-like wildcards are expanded before files are included. This means you can
66 use statements like the following:
68 Include "/etc/collectd.d/*.conf"
70 If more than one files are included by a single B<Include> option, the files
71 will be included in lexicographical order (as defined by the C<strcmp>
72 function). Thus, you can e.E<nbsp>g. use numbered prefixes to specify the
73 order in which the files are loaded.
75 To prevent loops and shooting yourself in the foot in interesting ways the
76 nesting is limited to a depth of 8E<nbsp>levels, which should be sufficient for
77 most uses. Since symlinks are followed it is still possible to crash the daemon
78 by looping symlinks. In our opinion significant stupidity should result in an
79 appropriate amount of pain.
81 It is no problem to have a block like C<E<lt>Plugin fooE<gt>> in more than one
82 file, but you cannot include files from within blocks.
84 =item B<PIDFile> I<File>
86 Sets where to write the PID file to. This file is overwritten when it exists
87 and deleted when the program is stopped. Some init-scripts might override this
88 setting using the B<-P> command-line option.
90 =item B<PluginDir> I<Directory>
92 Path to the plugins (shared objects) of collectd.
94 =item B<TypesDB> I<File> [I<File> ...]
96 Set one or more files that contain the data-set descriptions. See
97 L<types.db(5)> for a description of the format of this file.
99 =item B<Interval> I<Seconds>
101 Configures the interval in which to query the read plugins. Obviously smaller
102 values lead to a higher system load produced by collectd, while higher values
103 lead to more coarse statistics.
105 =item B<ReadThreads> I<Num>
107 Number of threads to start for reading plugins. The default value is B<5>, but
108 you may want to increase this if you have more than five plugins that take a
109 long time to read. Mostly those are plugin that do network-IO. Setting this to
110 a value higher than the number of plugins you've loaded is totally useless.
112 =item B<Hostname> I<Name>
114 Sets the hostname that identifies a host. If you omit this setting, the
115 hostname will be determinded using the L<gethostname(2)> system call.
117 =item B<FQDNLookup> B<true|false>
119 If B<Hostname> is determined automatically this setting controls whether or not
120 the daemon should try to figure out the "fully qualified domain name", FQDN.
121 This is done using a lookup of the name returned by C<gethostname>.
123 Using this feature (i.E<nbsp>e. setting this option to B<true>) is recommended.
124 However, to preserve backwards compatibility the default is set to B<false>.
125 The sample config file that is installed with C<makeE<nbsp>install> includes a
126 line which sets this option, though, so that default installations will have
127 this setting enabled.
129 =item B<PreCacheChain> I<ChainName>
131 =item B<PostCacheChain> I<ChainName>
133 Configure the name of the "pre-cache chain" and the "post-cache chain". Please
134 see L<FILTER CONFIGURATION> below on information on chains and how these
135 setting change the daemon's behavior.
139 =head1 PLUGIN OPTIONS
141 Some plugins may register own options. These options must be enclosed in a
142 C<Plugin>-Section. Which options exist depends on the plugin used. Some plugins
143 require external configuration, too. The C<apache plugin>, for example,
144 required C<mod_status> to be configured in the webserver you're going to
145 collect data from. These plugins are listed below as well, even if they don't
146 require any configuration within collectd's configfile.
148 A list of all plugins and a short summary for each plugin can be found in the
149 F<README> file shipped with the sourcecode and hopefully binary packets as
152 =head2 Plugin C<apache>
154 To configure the C<apache>-plugin you first need to configure the Apache
155 webserver correctly. The Apache-plugin C<mod_status> needs to be loaded and
156 working and the C<ExtendedStatus> directive needs to be B<enabled>. You can use
157 the following snipped to base your Apache config upon:
160 <IfModule mod_status.c>
161 <Location /mod_status>
162 SetHandler server-status
166 Since its C<mod_status> module is very similar to Apache's, B<lighttpd> is
167 also supported. It introduces a new field, called C<BusyServers>, to count the
168 number of currently connected clients. This field is also supported.
170 The following options are accepted by the C<apache>-plugin:
174 =item B<URL> I<http://host/mod_status?auto>
176 Sets the URL of the C<mod_status> output. This needs to be the output generated
177 by C<ExtendedStatus on> and it needs to be the machine readable output
178 generated by appending the C<?auto> argument.
180 =item B<User> I<Username>
182 Optional user name needed for authentication.
184 =item B<Password> I<Password>
186 Optional password needed for authentication.
188 =item B<VerifyPeer> B<true|false>
190 Enable or disable peer SSL certificate verification. See
191 L<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by default.
193 =item B<VerifyHost> B<true|false>
195 Enable or disable peer host name verification. If enabled, the plugin checks
196 if the C<Common Name> or a C<Subject Alternate Name> field of the SSL
197 certificate matches the host name provided by the B<URL> option. If this
198 identity check fails, the connection is aborted. Obviously, only works when
199 connecting to a SSL enabled server. Enabled by default.
201 =item B<CACert> I<File>
203 File that holds one or more SSL certificates. If you want to use HTTPS you will
204 possibly need this option. What CA certificates come bundled with C<libcurl>
205 and are checked by default depends on the distribution you use.
209 =head2 Plugin C<apcups>
213 =item B<Host> I<Hostname>
215 Hostname of the host running B<apcupsd>. Defaults to B<localhost>. Please note
216 that IPv6 support has been disabled unless someone can confirm or decline that
217 B<apcupsd> can handle it.
219 =item B<Port> I<Port>
221 TCP-Port to connect to. Defaults to B<3551>.
225 =head2 Plugin C<ascent>
227 This plugin collects information about an Ascent server, a free server for the
228 "World of Warcraft" game. This plugin gathers the information by fetching the
229 XML status page using C<libcurl> and parses it using C<libxml2>.
231 The configuration options are the same as for the C<apache> plugin above:
235 =item B<URL> I<http://localhost/ascent/status/>
237 Sets the URL of the XML status output.
239 =item B<User> I<Username>
241 Optional user name needed for authentication.
243 =item B<Password> I<Password>
245 Optional password needed for authentication.
247 =item B<VerifyPeer> B<true|false>
249 Enable or disable peer SSL certificate verification. See
250 L<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by default.
252 =item B<VerifyHost> B<true|false>
254 Enable or disable peer host name verification. If enabled, the plugin checks
255 if the C<Common Name> or a C<Subject Alternate Name> field of the SSL
256 certificate matches the host name provided by the B<URL> option. If this
257 identity check fails, the connection is aborted. Obviously, only works when
258 connecting to a SSL enabled server. Enabled by default.
260 =item B<CACert> I<File>
262 File that holds one or more SSL certificates. If you want to use HTTPS you will
263 possibly need this option. What CA certificates come bundled with C<libcurl>
264 and are checked by default depends on the distribution you use.
268 =head2 Plugin C<bind>
270 Starting with BIND 9.5.0, the most widely used DNS server software provides
271 extensive statistics about queries, responses and lots of other information.
272 The bind plugin retrieves this information that's encoded in XML and provided
273 via HTTP and submits the values to collectd.
275 To use this plugin, you first need to tell BIND to make this information
276 available. This is done with the C<statistics-channels> configuration option:
278 statistics-channels {
279 inet localhost port 8053;
282 The configuration follows the grouping that can be seen when looking at the
283 data with an XSLT compatible viewer, such as a modern web browser. It's
284 probably a good idea to make yourself familiar with the provided values, so you
285 can understand what the collected statistics actually mean.
290 URL "http://localhost:8053/"
304 Zone "127.in-addr.arpa/IN"
308 The bind plugin accepts the following configuration options:
314 URL from which to retrieve the XML data. If not specified,
315 C<http://localhost:8053/> will be used.
317 =item B<OpCodes> I<true>|I<false>
319 When enabled, statistics about the I<"OpCodes">, for example the number of
320 C<QUERY> packets, are collected.
324 =item B<QTypes> I<true>|I<false>
326 When enabled, the number of I<incoming> queries by query types (for example
327 C<A>, C<MX>, C<AAAA>) is collected.
331 =item B<ServerStats> I<true>|I<false>
333 Collect global server statistics, such as requests received over IPv4 and IPv6,
334 successful queries, and failed updates.
338 =item B<ZoneMaintStats> I<true>|I<false>
340 Collect zone maintenance statistics, mostly information about notifications
341 (zone updates) and zone transfers.
345 =item B<ResolverStats> I<true>|I<false>
347 Collect resolver statistics, i.E<nbsp>e. statistics about outgoing requests
348 (e.E<nbsp>g. queries over IPv4, lame servers). Since the global resolver
349 counters apparently were removed in BIND 9.5.1 and 9.6.0, this is disabled by
350 default. Use the B<ResolverStats> option within a B<View "_default"> block
351 instead for the same functionality.
357 Collect global memory statistics.
361 =item B<View> I<Name>
363 Collect statistics about a specific I<"view">. BIND can behave different,
364 mostly depending on the source IP-address of the request. These different
365 configurations are called "views". If you don't use this feature, you most
366 likely are only interested in the C<_default> view.
368 Within a E<lt>B<View>E<nbsp>I<name>E<gt> block, you can specify which
369 information you want to collect about a view. If no B<View> block is
370 configured, no detailed view statistics will be collected.
374 =item B<QTypes> I<true>|I<false>
376 If enabled, the number of I<outgoing> queries by query type (e.E<nbsp>g. C<A>,
381 =item B<ResolverStats> I<true>|I<false>
383 Collect resolver statistics, i.E<nbsp>e. statistics about outgoing requests
384 (e.E<nbsp>g. queries over IPv4, lame servers).
388 =item B<CacheRRSets> I<true>|I<false>
390 If enabled, the number of entries (I<"RR sets">) in the view's cache by query
391 type is collected. Negative entries (queries which resulted in an error, for
392 example names that do not exist) are reported with a leading exclamation mark,
397 =item B<Zone> I<Name>
399 When given, collect detailed information about the given zone in the view. The
400 information collected if very similar to the global B<ServerStats> information
403 You can repeat this option to collect detailed information about multiple
406 By default no detailed zone information is collected.
412 =head2 Plugin C<couchdb>
414 The couchdb plugin uses B<libcurl> (L<http://curl.haxx.se/>) and B<libyajl>
415 (L<http://www.lloydforge.org/projects/yajl/>) to collect values from CouchDB
416 documents (stored JSON notation).
418 The following example will collect several values from the built-in `_stats'
419 runtime statistics module (L<http://wiki.apache.org/couchdb/Runtime_Statistics>).
422 <URL "http://localhost:5984/_stats">
424 <Key "httpd/requests/count">
428 <Key "httpd_request_methods/*/count">
429 Type "http_request_methods"
432 <Key "httpd_status_codes/*/count">
433 Type "http_response_codes"
438 The following example will collect the status values from each database:
440 <URL "http://localhost:5984/_all_dbs">
445 <Key "*/doc_del_count">
453 In the B<Plugin> block, there may be one or more B<URL> blocks, each defining
454 a URL to be fetched via HTTP (libcurl) and one or more B<Key> blocks.
455 The B<Key> string argument must be in a path format, of which is used to collect
456 a value from a JSON map object. If a B<Key> path element is that of a I<*> wildcard,
457 the values for all keys will be collectd.
459 The following options are valid within B<URL> blocks:
463 =item B<Instance> I<Instance>
465 Sets the plugin instance to I<Instance>.
467 =item B<User> I<Name>
469 Username to use if authorization is required to read the page.
471 =item B<Password> I<Password>
473 Password to use if authorization is required to read the page.
475 =item B<VerifyPeer> B<true>|B<false>
477 Enable or disable peer SSL certificate verification. See
478 L<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by default.
480 =item B<VerifyHost> B<true>|B<false>
482 Enable or disable peer host name verification. If enabled, the plugin checks if
483 the C<Common Name> or a C<Subject Alternate Name> field of the SSL certificate
484 matches the host name provided by the B<URL> option. If this identity check
485 fails, the connection is aborted. Obviously, only works when connecting to a
486 SSL enabled server. Enabled by default.
488 =item B<CACert> I<file>
490 File that holds one or more SSL certificates. If you want to use HTTPS you will
491 possibly need this option. What CA certificates come bundled with C<libcurl>
492 and are checked by default depends on the distribution you use.
496 The following options are valid within B<Key> blocks:
500 =item B<Type> I<Type>
502 Sets the type used to dispatch the values to the daemon. Detailed information
503 about types and their configuration can be found in L<types.db(5)>. This
506 =item B<Instance> I<Instance>
508 Type-instance to use. Defaults to the current map key or current string array element value.
512 =head2 Plugin C<cpufreq>
514 This plugin doesn't have any options. It reads
515 F</sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq> (for the first CPU
516 installed) to get the current CPU frequency. If this file does not exist make
517 sure B<cpufreqd> (L<http://cpufreqd.sourceforge.net/>) or a similar tool is
518 installed and an "cpu governor" (that's a kernel module) is loaded.
524 =item B<DataDir> I<Directory>
526 Set the directory to store CSV-files under. Per default CSV-files are generated
527 beneath the daemon's working directory, i.E<nbsp>e. the B<BaseDir>.
528 The special strings B<stdout> and B<stderr> can be used to write to the standard
529 output and standard error channels, respectively. This, of course, only makes
530 much sense when collectd is running in foreground- or non-daemon-mode.
532 =item B<StoreRates> B<true|false>
534 If set to B<true>, convert counter values to rates. If set to B<false> (the
535 default) counter values are stored as is, i.E<nbsp>e. as an increasing integer
540 =head2 Plugin C<curl>
542 The curl plugin uses the B<libcurl> (L<http://curl.haxx.se/>) to read web pages
543 and the match infrastructure (the same code used by the tail plugin) to use
544 regular expressions with the received data.
546 The following example will read the current value of AMD stock from google's
547 finance page and dispatch the value to collectd.
550 <Page "stock_quotes">
551 URL "http://finance.google.com/finance?q=NYSE%3AAMD"
555 Regex "<span +class=\"pr\"[^>]*> *([0-9]*\\.[0-9]+) *</span>"
556 DSType "GaugeAverage"
557 # Note: `stock_value' is not a standard type.
564 In the B<Plugin> block, there may be one or more B<Page> blocks, each defining
565 a web page and one or more "matches" to be performed on the returned data. The
566 string argument to the B<Page> block is used as plugin instance.
568 The following options are valid within B<Page> blocks:
574 URL of the web site to retrieve. Since a regular expression will be used to
575 extract information from this data, non-binary data is a big plus here ;)
577 =item B<User> I<Name>
579 Username to use if authorization is required to read the page.
581 =item B<Password> I<Password>
583 Password to use if authorization is required to read the page.
585 =item B<VerifyPeer> B<true>|B<false>
587 Enable or disable peer SSL certificate verification. See
588 L<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by default.
590 =item B<VerifyHost> B<true>|B<false>
592 Enable or disable peer host name verification. If enabled, the plugin checks if
593 the C<Common Name> or a C<Subject Alternate Name> field of the SSL certificate
594 matches the host name provided by the B<URL> option. If this identity check
595 fails, the connection is aborted. Obviously, only works when connecting to a
596 SSL enabled server. Enabled by default.
598 =item B<CACert> I<file>
600 File that holds one or more SSL certificates. If you want to use HTTPS you will
601 possibly need this option. What CA certificates come bundled with C<libcurl>
602 and are checked by default depends on the distribution you use.
604 =item B<E<lt>MatchE<gt>>
606 One or more B<Match> blocks that define how to match information in the data
607 returned by C<libcurl>. The C<curl> plugin uses the same infrastructure that's
608 used by the C<tail> plugin, so please see the documentation of the C<tail>
609 plugin below on how matches are defined.
615 This plugin uses the B<dbi> library (L<http://libdbi.sourceforge.net/>) to
616 connect to various databases, execute I<SQL> statements and read back the
617 results. I<dbi> is an acronym for "database interface" in case you were
618 wondering about the name. You can configure how each column is to be
619 interpreted and the plugin will generate one or more data sets from each row
620 returned according to these rules.
622 Because the plugin is very generic, the configuration is a little more complex
623 than those of other plugins. It usually looks something like this:
626 <Query "out_of_stock">
627 Statement "SELECT category, COUNT(*) AS value FROM products WHERE in_stock = 0 GROUP BY category"
628 # Use with MySQL 5.0.0 or later
632 InstancePrefix "out_of_stock"
633 InstancesFrom "category"
637 <Database "product_information">
639 DriverOption "host" "localhost"
640 DriverOption "username" "collectd"
641 DriverOption "password" "aZo6daiw"
642 DriverOption "dbname" "prod_info"
648 The configuration above defines one query with one result and one database. The
649 query is then linked to the database with the B<Query> option I<within> the
650 B<E<lt>DatabaseE<gt>> block. You can have any number of queries and databases
651 and you can also use the B<Include> statement to split up the configuration
652 file in multiple, smaller files. However, the B<E<lt>QueryE<gt>> block I<must>
653 precede the B<E<lt>DatabaseE<gt>> blocks, because the file is interpreted from
656 The following is a complete list of options:
658 =head3 B<Query> blocks
660 Query blocks define I<SQL> statements and how the returned data should be
661 interpreted. They are identified by the name that is given in the opening line
662 of the block. Thus the name needs to be unique. Other than that, the name is
663 not used in collectd.
665 In each B<Query> block, there is one or more B<Result> blocks. B<Result> blocks
666 define which column holds which value or instance information. You can use
667 multiple B<Result> blocks to create multiple values from one returned row. This
668 is especially useful, when queries take a long time and sending almost the same
669 query again and again is not desirable.
673 <Query "environment">
674 Statement "select station, temperature, humidity from environment"
677 # InstancePrefix "foo"
678 InstancesFrom "station"
679 ValuesFrom "temperature"
683 InstancesFrom "station"
684 ValuesFrom "humidity"
688 The following options are accepted:
692 =item B<Statement> I<SQL>
694 Sets the statement that should be executed on the server. This is B<not>
695 interpreted by collectd, but simply passed to the database server. Therefore,
696 the SQL dialect that's used depends on the server collectd is connected to.
698 The query has to return at least two columns, one for the instance and one
699 value. You cannot omit the instance, even if the statement is guaranteed to
700 always return exactly one line. In that case, you can usually specify something
703 Statement "SELECT \"instance\", COUNT(*) AS value FROM table"
705 (That works with MySQL but may not be valid SQL according to the spec. If you
706 use a more strict database server, you may have to select from a dummy table or
709 Please note that some databases, for example B<Oracle>, will fail if you
710 include a semicolon at the end of the statement.
712 =item B<MinVersion> I<Version>
714 =item B<MaxVersion> I<Value>
716 Only use this query for the specified database version. You can use these
717 options to provide multiple queries with the same name but with a slightly
718 different syntax. The plugin will use only those queries, where the specified
719 minimum and maximum versions fit the version of the database in use.
721 The database version is determined by C<dbi_conn_get_engine_version>, see the
722 L<libdbi documentation|http://libdbi.sourceforge.net/docs/programmers-guide/reference-conn.html#DBI-CONN-GET-ENGINE-VERSION>
723 for details. Basically, each part of the version is assumed to be in the range
724 from B<00> to B<99> and all dots are removed. So version "4.1.2" becomes
725 "40102", version "5.0.42" becomes "50042".
727 B<Warning:> The plugin will use B<all> matching queries, so if you specify
728 multiple queries with the same name and B<overlapping> ranges, weird stuff will
729 happen. Don't to it! A valid example would be something along these lines:
740 In the above example, there are three ranges that don't overlap. The last one
741 goes from version "5.1.0" to infinity, meaning "all later versions". Versions
742 before "4.0.0" are not specified.
744 =item B<Type> I<Type>
746 The B<type> that's used for each line returned. See L<types.db(5)> for more
747 details on how types are defined. In short: A type is a predefined layout of
748 data and the number of values and type of values has to match the type
751 If you specify "temperature" here, you need exactly one gauge column. If you
752 specify "if_octets", you will need two counter columns. See the B<ValuesFrom>
755 There must be exactly one B<Type> option inside each B<Result> block.
757 =item B<InstancePrefix> I<prefix>
759 Prepends I<prefix> to the type instance. If B<InstancesFrom> (see below) is not
760 given, the string is simply copied. If B<InstancesFrom> is given, I<prefix> and
761 all strings returned in the appropriate columns are concatenated together,
762 separated by dashes I<("-")>.
764 =item B<InstancesFrom> I<column0> [I<column1> ...]
766 Specifies the columns whose values will be used to create the "type-instance"
767 for each row. If you specify more than one column, the value of all columns
768 will be joined together with dashes I<("-")> as separation characters.
770 The plugin itself does not check whether or not all built instances are
771 different. It's your responsibility to assure that each is unique. This is
772 especially true, if you do not specify B<InstancesFrom>: B<You> have to make
773 sure that only one row is returned in this case.
775 If neither B<InstancePrefix> nor B<InstancesFrom> is given, the type-instance
778 =item B<ValuesFrom> I<column0> [I<column1> ...]
780 Names the columns whose content is used as the actual data for the data sets
781 that are dispatched to the daemon. How many such columns you need is determined
782 by the B<Type> setting above. If you specify too many or not enough columns,
783 the plugin will complain about that and no data will be submitted to the
786 The actual data type in the columns is not that important. The plugin will
787 automatically cast the values to the right type if it know how to do that. So
788 it should be able to handle integer an floating point types, as well as strings
789 (if they include a number at the beginning).
791 There must be at least one B<ValuesFrom> option inside each B<Result> block.
795 =head3 B<Database> blocks
797 Database blocks define a connection to a database and which queries should be
798 sent to that database. Since the used "dbi" library can handle a wide variety
799 of databases, the configuration is very generic. If in doubt, refer to libdbi's
800 documentationE<nbsp>- we stick as close to the terminology used there.
802 Each database needs a "name" as string argument in the starting tag of the
803 block. This name will be used as "PluginInstance" in the values submitted to
804 the daemon. Other than that, that name is not used.
808 =item B<Driver> I<Driver>
810 Specifies the driver to use to connect to the database. In many cases those
811 drivers are named after the database they can connect to, but this is not a
812 technical necessity. These drivers are sometimes referred to as "DBD",
813 B<D>ataB<B>ase B<D>river, and some distributions ship them in separate
814 packages. Drivers for the "dbi" library are developed by the B<libdbi-drivers>
815 project at L<http://libdbi-drivers.sourceforge.net/>.
817 You need to give the driver name as expected by the "dbi" library here. You
818 should be able to find that in the documentation for each driver. If you
819 mistype the driver name, the plugin will dump a list of all known driver names
822 =item B<DriverOption> I<Key> I<Value>
824 Sets driver-specific options. What option a driver supports can be found in the
825 documentation for each driver, somewhere at
826 L<http://libdbi-drivers.sourceforge.net/>. However, the options "host",
827 "username", "password", and "dbname" seem to be deE<nbsp>facto standards.
829 Unfortunately, drivers are not too keen to report errors when an unknown option
830 is passed to them, so invalid settings here may go unnoticed. This is not the
831 plugin's fault, it will report errors if it gets them from the libraryE<nbsp>/
832 the driver. If a driver complains about an option, the plugin will dump a
833 complete list of all options understood by that driver to the log.
835 =item B<SelectDB> I<Database>
837 In some cases, the database name you connect with is not the database name you
838 want to use for querying data. If this option is set, the plugin will "select"
839 (switch to) that database after the connection is established.
841 =item B<Query> I<QueryName>
843 Associates the query named I<QueryName> with this database connection. The
844 query needs to be defined I<before> this statement, i.E<nbsp>e. all query
845 blocks you want to refer to must be placed above the database block you want to
854 =item B<Device> I<Device>
856 Select partitions based on the devicename.
858 =item B<MountPoint> I<Directory>
860 Select partitions based on the mountpoint.
862 =item B<FSType> I<FSType>
864 Select partitions based on the filesystem type.
866 =item B<IgnoreSelected> I<true>|I<false>
868 Invert the selection: If set to true, all partitions B<except> the ones that
869 match any one of the criteria are collected. By default only selected
870 partitions are collected if a selection is made. If no selection is configured
871 at all, B<all> partitions are selected.
875 =head2 Plugin C<disk>
877 The C<disk> plugin collects information about the usage of physical disks and
878 logical disks (partitions). Values collected are the number of octets written
879 to and read from a disk or partition, the number of read/write operations
880 issued to the disk and a rather complex "time" it took for these commands to be
883 Using the following two options you can ignore some disks or configure the
884 collection only of specific disks.
888 =item B<Disk> I<Name>
890 Select the disk I<Name>. Whether it is collected or ignored depends on the
891 B<IgnoreSelected> setting, see below. As with other plugins that use the
892 daemon's ignorelist functionality, a string that starts and ends with a slash
893 is interpreted as a regular expression. Examples:
898 =item B<IgnoreSelected> B<true>|B<false>
900 Sets whether selected disks, i.E<nbsp>e. the ones matches by any of the B<Disk>
901 statements, are ignored or if all other disks are ignored. The behavior
902 (hopefully) is intuitive: If no B<Disk> option is configured, all disks are
903 collected. If at least one B<Disk> option is given and no B<IgnoreSelected> or
904 set to B<false>, B<only> matching disks will be collected. If B<IgnoreSelected>
905 is set to B<true>, all disks are collected B<except> the ones matched.
913 =item B<Interface> I<Interface>
915 The dns plugin uses B<libpcap> to capture dns traffic and analyses it. This
916 option sets the interface that should be used. If this option is not set, or
917 set to "any", the plugin will try to get packets from B<all> interfaces. This
918 may not work on certain platforms, such as MacE<nbsp>OSE<nbsp>X.
920 =item B<IgnoreSource> I<IP-address>
922 Ignore packets that originate from this address.
926 =head2 Plugin C<email>
930 =item B<SocketFile> I<Path>
932 Sets the socket-file which is to be created.
934 =item B<SocketGroup> I<Group>
936 If running as root change the group of the UNIX-socket after it has been
937 created. Defaults to B<collectd>.
939 =item B<SocketPerms> I<Permissions>
941 Change the file permissions of the UNIX-socket after it has been created. The
942 permissions must be given as a numeric, octal value as you would pass to
943 L<chmod(1)>. Defaults to B<0770>.
945 =item B<MaxConns> I<Number>
947 Sets the maximum number of connections that can be handled in parallel. Since
948 this many threads will be started immediately setting this to a very high
949 value will waste valuable resources. Defaults to B<5> and will be forced to be
950 at most B<16384> to prevent typos and dumb mistakes.
954 =head2 Plugin C<exec>
956 Please make sure to read L<collectd-exec(5)> before using this plugin. It
957 contains valuable information on when the executable is executed and the
958 output that is expected from it.
962 =item B<Exec> I<User>[:[I<Group>]] I<Executable> [I<E<lt>argE<gt>> [I<E<lt>argE<gt>> ...]]
964 =item B<NotificationExec> I<User>[:[I<Group>]] I<Executable> [I<E<lt>argE<gt>> [I<E<lt>argE<gt>> ...]]
966 Execute the executable I<Executable> as user I<User>. If the user name is
967 followed by a colon and a group name, the effective group is set to that group.
968 The real group and saved-set group will be set to the default group of that
969 user. If no group is given the effective group ID will be the same as the real
972 Please note that in order to change the user and/or group the daemon needs
973 superuser privileges. If the daemon is run as an unprivileged user you must
974 specify the same user/group here. If the daemon is run with superuser
975 privileges, you must supply a non-root user here.
977 The executable may be followed by optional arguments that are passed to the
978 program. Please note that due to the configuration parsing numbers and boolean
979 values may be changed. If you want to be absolutely sure that something is
980 passed as-is please enclose it in quotes.
982 The B<Exec> and B<NotificationExec> statements change the semantics of the
983 programs executed, i.E<nbsp>e. the data passed to them and the response
984 expected from them. This is documented in great detail in L<collectd-exec(5)>.
988 =head2 Plugin C<filecount>
990 The C<filecount> plugin counts the number of files in a certain directory (and
991 its subdirectories) and their combined size. The configuration is very straight
995 <Directory "/var/qmail/queue/mess">
996 Instance "qmail-message"
998 <Directory "/var/qmail/queue/todo">
999 Instance "qmail-todo"
1001 <Directory "/var/lib/php5">
1002 Instance "php5-sessions"
1007 The example above counts the number of files in QMail's queue directories and
1008 the number of PHP5 sessions. Jfiy: The "todo" queue holds the messages that
1009 QMail has not yet looked at, the "message" queue holds the messages that were
1010 classified into "local" and "remote".
1012 As you can see, the configuration consists of one or more C<Directory> blocks,
1013 each of which specifies a directory in which to count the files. Within those
1014 blocks, the following options are recognized:
1018 =item B<Instance> I<Instance>
1020 Sets the plugin instance to I<Instance>. That instance name must be unique, but
1021 it's your responsibility, the plugin doesn't check for that. If not given, the
1022 instance is set to the directory name with all slashes replaced by underscores
1023 and all leading underscores removed.
1025 =item B<Name> I<Pattern>
1027 Only count files that match I<Pattern>, where I<Pattern> is a shell-like
1028 wildcard as understood by L<fnmatch(3)>. Only the B<filename> is checked
1029 against the pattern, not the entire path. In case this makes it easier for you:
1030 This option has been named after the B<-name> parameter to L<find(1)>.
1032 =item B<MTime> I<Age>
1034 Count only files of a specific age: If I<Age> is greater than zero, only files
1035 that haven't been touched in the last I<Age> seconds are counted. If I<Age> is
1036 a negative number, this is inversed. For example, if B<-60> is specified, only
1037 files that have been modified in the last minute will be counted.
1039 The number can also be followed by a "multiplier" to easily specify a larger
1040 timespan. When given in this notation, the argument must in quoted, i.E<nbsp>e.
1041 must be passed as string. So the B<-60> could also be written as B<"-1m"> (one
1042 minute). Valid multipliers are C<s> (second), C<m> (minute), C<h> (hour), C<d>
1043 (day), C<w> (week), and C<y> (year). There is no "month" multiplier. You can
1044 also specify fractional numbers, e.E<nbsp>g. B<"0.5d"> is identical to
1047 =item B<Size> I<Size>
1049 Count only files of a specific size. When I<Size> is a positive number, only
1050 files that are at least this big are counted. If I<Size> is a negative number,
1051 this is inversed, i.E<nbsp>e. only files smaller than the absolute value of
1052 I<Size> are counted.
1054 As with the B<MTime> option, a "multiplier" may be added. For a detailed
1055 description see above. Valid multipliers here are C<b> (byte), C<k> (kilobyte),
1056 C<m> (megabyte), C<g> (gigabyte), C<t> (terabyte), and C<p> (petabyte). Please
1057 note that there are 1000 bytes in a kilobyte, not 1024.
1059 =item B<Recursive> I<true>|I<false>
1061 Controls whether or not to recurse into subdirectories. Enabled by default.
1065 =head2 Plugin C<gmond>
1067 The I<gmond> plugin received the multicast traffic sent by B<gmond>, the
1068 statistics collection daemon of Ganglia. Mappings for the standard "metrics"
1069 are built-in, custom mappings may be added via B<Metric> blocks, see below.
1074 MCReceiveFrom "239.2.11.71" "8649"
1075 <Metric "swap_total">
1077 TypeInstance "total"
1080 <Metric "swap_free">
1087 The following metrics are built-in:
1093 load_one, load_five, load_fifteen
1097 cpu_user, cpu_system, cpu_idle, cpu_nice, cpu_wio
1101 mem_free, mem_shared, mem_buffers, mem_cached, mem_total
1113 Available configuration options:
1117 =item B<MCReceiveFrom> I<MCGroup> [I<Port>]
1119 Sets sets the multicast group and UDP port to which to subscribe.
1121 Default: B<239.2.11.71>E<nbsp>/E<nbsp>B<8649>
1123 =item E<lt>B<Metric> I<Name>E<gt>
1125 These blocks add a new metric conversion to the internal table. I<Name>, the
1126 string argument to the B<Metric> block, is the metric name as used by Ganglia.
1130 =item B<Type> I<Type>
1132 Type to map this metric to. Required.
1134 =item B<TypeInstance> I<Instance>
1136 Type-instance to use. Optional.
1138 =item B<DataSource> I<Name>
1140 Data source to map this metric to. If the configured type has exactly one data
1141 source, this is optional. Otherwise the option is required.
1147 =head2 Plugin C<hddtemp>
1149 To get values from B<hddtemp> collectd connects to B<localhost> (127.0.0.1),
1150 port B<7634/tcp>. The B<Host> and B<Port> options can be used to change these
1151 default values, see below. C<hddtemp> has to be running to work correctly. If
1152 C<hddtemp> is not running timeouts may appear which may interfere with other
1155 The B<hddtemp> homepage can be found at
1156 L<http://www.guzu.net/linux/hddtemp.php>.
1160 =item B<Host> I<Hostname>
1162 Hostname to connect to. Defaults to B<127.0.0.1>.
1164 =item B<Port> I<Port>
1166 TCP-Port to connect to. Defaults to B<7634>.
1168 =item B<TranslateDevicename> I<true>|I<false>
1170 If enabled, translate the disk names to major/minor device numbers
1171 (e.E<nbsp>g. "8-0" for /dev/sda). For backwards compatibility this defaults to
1172 I<true> but it's recommended to disable it as it will probably be removed in
1173 the next major version.
1177 =head2 Plugin C<interface>
1181 =item B<Interface> I<Interface>
1183 Select this interface. By default these interfaces will then be collected. For
1184 a more detailed description see B<IgnoreSelected> below.
1186 =item B<IgnoreSelected> I<true>|I<false>
1188 If no configuration if given, the B<traffic>-plugin will collect data from
1189 all interfaces. This may not be practical, especially for loopback- and
1190 similar interfaces. Thus, you can use the B<Interface>-option to pick the
1191 interfaces you're interested in. Sometimes, however, it's easier/preferred
1192 to collect all interfaces I<except> a few ones. This option enables you to
1193 do that: By setting B<IgnoreSelected> to I<true> the effect of
1194 B<Interface> is inverted: All selected interfaces are ignored and all
1195 other interfaces are collected.
1199 =head2 Plugin C<ipmi>
1203 =item B<Sensor> I<Sensor>
1205 Selects sensors to collect or to ignore, depending on B<IgnoreSelected>.
1207 =item B<IgnoreSelected> I<true>|I<false>
1209 If no configuration if given, the B<ipmi> plugin will collect data from all
1210 sensors found of type "temperature", "voltage", "current" and "fanspeed".
1211 This option enables you to do that: By setting B<IgnoreSelected> to I<true>
1212 the effect of B<Sensor> is inverted: All selected sensors are ignored and
1213 all other sensors are collected.
1215 =item B<NotifySensorAdd> I<true>|I<false>
1217 If a sensor appears after initialization time of a minute a notification
1220 =item B<NotifySensorRemove> I<true>|I<false>
1222 If a sensor disappears a notification is sent.
1224 =item B<NotifySensorNotPresent> I<true>|I<false>
1226 If you have for example dual power supply and one of them is (un)plugged then
1227 a notification is sent.
1231 =head2 Plugin C<iptables>
1235 =item B<Chain> I<Table> I<Chain> [I<Comment|Number> [I<Name>]]
1237 Select the rules to count. If only I<Table> and I<Chain> are given, this plugin
1238 will collect the counters of all rules which have a comment-match. The comment
1239 is then used as type-instance.
1241 If I<Comment> or I<Number> is given, only the rule with the matching comment or
1242 the I<n>th rule will be collected. Again, the comment (or the number) will be
1243 used as the type-instance.
1245 If I<Name> is supplied, it will be used as the type-instance instead of the
1246 comment or the number.
1250 =head2 Plugin C<irq>
1256 Select this irq. By default these irqs will then be collected. For a more
1257 detailed description see B<IgnoreSelected> below.
1259 =item B<IgnoreSelected> I<true>|I<false>
1261 If no configuration if given, the B<irq>-plugin will collect data from all
1262 irqs. This may not be practical, especially if no interrupts happen. Thus, you
1263 can use the B<Irq>-option to pick the interrupt you're interested in.
1264 Sometimes, however, it's easier/preferred to collect all interrupts I<except> a
1265 few ones. This option enables you to do that: By setting B<IgnoreSelected> to
1266 I<true> the effect of B<Irq> is inverted: All selected interrupts are ignored
1267 and all other interrupts are collected.
1271 =head2 Plugin C<java>
1273 The I<Java> plugin makes it possible to write extensions for collectd in Java.
1274 This section only discusses the syntax and semantic of the configuration
1275 options. For more in-depth information on the I<Java> plugin, please read
1276 L<collectd-java(5)>.
1281 JVMArg "-verbose:jni"
1282 JVMArg "-Djava.class.path=/opt/collectd/lib/collectd/bindings/java"
1283 LoadPlugin "org.collectd.java.Foobar"
1284 <Plugin "org.collectd.java.Foobar">
1285 # To be parsed by the plugin
1289 Available configuration options:
1293 =item B<JVMArg> I<Argument>
1295 Argument that is to be passed to the I<Java Virtual Machine> (JVM). This works
1296 exactly the way the arguments to the I<java> binary on the command line work.
1297 Execute C<javaE<nbsp>--help> for details.
1299 Please note that B<all> these options must appear B<before> (i.E<nbsp>e. above)
1300 any other options! When another option is found, the JVM will be started and
1301 later options will have to be ignored!
1303 =item B<LoadPlugin> I<JavaClass>
1305 Instantiates a new I<JavaClass> object. The constructor of this object very
1306 likely then registers one or more callback methods with the server.
1308 See L<collectd-java(5)> for details.
1310 When the first such option is found, the virtual machine (JVM) is created. This
1311 means that all B<JVMArg> options must appear before (i.E<nbsp>e. above) all
1312 B<LoadPlugin> options!
1314 =item B<Plugin> I<Name>
1316 The entire block is passed to the Java plugin as an
1317 I<org.collectd.api.OConfigItem> object.
1319 For this to work, the plugin has to register a configuration callback first,
1320 see L<collectd-java(5)/"config callback">. This means, that the B<Plugin> block
1321 must appear after the appropriate B<LoadPlugin> block. Also note, that I<Name>
1322 depends on the (Java) plugin registering the callback and is completely
1323 independent from the I<JavaClass> argument passed to B<LoadPlugin>.
1327 =head2 Plugin C<libvirt>
1329 This plugin allows CPU, disk and network load to be collected for virtualized
1330 guests on the machine. This means that these characteristics can be collected
1331 for guest systems without installing any software on them - collectd only runs
1332 on the hosting system. The statistics are collected through libvirt
1333 (L<http://libvirt.org/>).
1335 Only I<Connection> is required.
1339 =item B<Connection> I<uri>
1341 Connect to the hypervisor given by I<uri>. For example if using Xen use:
1343 Connection "xen:///"
1345 Details which URIs allowed are given at L<http://libvirt.org/uri.html>.
1347 =item B<RefreshInterval> I<seconds>
1349 Refresh the list of domains and devices every I<seconds>. The default is 60
1350 seconds. Setting this to be the same or smaller than the I<Interval> will cause
1351 the list of domains and devices to be refreshed on every iteration.
1353 Refreshing the devices in particular is quite a costly operation, so if your
1354 virtualization setup is static you might consider increasing this. If this
1355 option is set to 0, refreshing is disabled completely.
1357 =item B<Domain> I<name>
1359 =item B<BlockDevice> I<name:dev>
1361 =item B<InterfaceDevice> I<name:dev>
1363 =item B<IgnoreSelected> I<true>|I<false>
1365 Select which domains and devices are collected.
1367 If I<IgnoreSelected> is not given or I<false> then only the listed domains and
1368 disk/network devices are collected.
1370 If I<IgnoreSelected> is I<true> then the test is reversed and the listed
1371 domains and disk/network devices are ignored, while the rest are collected.
1373 The domain name and device names may use a regular expression, if the name is
1374 surrounded by I</.../> and collectd was compiled with support for regexps.
1376 The default is to collect statistics for all domains and all their devices.
1380 BlockDevice "/:hdb/"
1381 IgnoreSelected "true"
1383 Ignore all I<hdb> devices on any domain, but other block devices (eg. I<hda>)
1386 =item B<HostnameFormat> B<name|uuid|hostname|...>
1388 When the libvirt plugin logs data, it sets the hostname of the collected data
1389 according to this setting. The default is to use the guest name as provided by
1390 the hypervisor, which is equal to setting B<name>.
1392 B<uuid> means use the guest's UUID. This is useful if you want to track the
1393 same guest across migrations.
1395 B<hostname> means to use the global B<Hostname> setting, which is probably not
1396 useful on its own because all guests will appear to have the same name.
1398 You can also specify combinations of these fields. For example B<name uuid>
1399 means to concatenate the guest name and UUID (with a literal colon character
1400 between, thus I<"foo:1234-1234-1234-1234">).
1404 =head2 Plugin C<logfile>
1408 =item B<LogLevel> B<debug|info|notice|warning|err>
1410 Sets the log-level. If, for example, set to B<notice>, then all events with
1411 severity B<notice>, B<warning>, or B<err> will be written to the logfile.
1413 Please note that B<debug> is only available if collectd has been compiled with
1416 =item B<File> I<File>
1418 Sets the file to write log messages to. The special strings B<stdout> and
1419 B<stderr> can be used to write to the standard output and standard error
1420 channels, respectively. This, of course, only makes much sense when collectd is
1421 running in foreground- or non-daemon-mode.
1423 =item B<Timestamp> B<true>|B<false>
1425 Prefix all lines printed by the current time. Defaults to B<true>.
1429 B<Note>: There is no need to notify the daemon after moving or removing the
1430 log file (e.E<nbsp>g. when rotating the logs). The plugin reopens the file
1431 for each line it writes.
1433 =head2 Plugin C<mbmon>
1435 The C<mbmon plugin> uses mbmon to retrieve temperature, voltage, etc.
1437 Be default collectd connects to B<localhost> (127.0.0.1), port B<411/tcp>. The
1438 B<Host> and B<Port> options can be used to change these values, see below.
1439 C<mbmon> has to be running to work correctly. If C<mbmon> is not running
1440 timeouts may appear which may interfere with other statistics..
1442 C<mbmon> must be run with the -r option ("print TAG and Value format");
1443 Debian's F</etc/init.d/mbmon> script already does this, other people
1444 will need to ensure that this is the case.
1448 =item B<Host> I<Hostname>
1450 Hostname to connect to. Defaults to B<127.0.0.1>.
1452 =item B<Port> I<Port>
1454 TCP-Port to connect to. Defaults to B<411>.
1458 =head2 Plugin C<memcachec>
1460 The C<memcachec plugin> connects to a memcached server, queries one or more
1461 given I<pages> and parses the returned data according to user specification.
1462 The I<matches> used are the same as the matches used in the C<curl> and C<tail>
1465 In order to talk to the memcached server, this plugin uses the I<libmemcached>
1466 library. Please note that there is another library with a very similar name,
1467 libmemcache (notice the missing `d'), which is not applicable.
1469 Synopsis of the configuration:
1471 <Plugin "memcachec">
1472 <Page "plugin_instance">
1476 Regex "(\\d+) bytes sent"
1479 Instance "type_instance"
1484 The configuration options are:
1488 =item E<lt>B<Page> I<Name>E<gt>
1490 Each B<Page> block defines one I<page> to be queried from the memcached server.
1491 The block requires one string argument which is used as I<plugin instance>.
1493 =item B<Server> I<Address>
1495 Sets the server address to connect to when querying the page. Must be inside a
1500 When connected to the memcached server, asks for the page I<Key>.
1502 =item E<lt>B<Match>E<gt>
1504 Match blocks define which strings to look for and how matches substrings are
1505 interpreted. For a description of match blocks, please see L<"Plugin tail">.
1509 =head2 Plugin C<memcached>
1511 The C<memcached plugin> connects to a memcached server and queries statistics
1512 about cache utilization, memory and bandwidth used.
1513 L<http://www.danga.com/memcached/>
1517 =item B<Host> I<Hostname>
1519 Hostname to connect to. Defaults to B<127.0.0.1>.
1521 =item B<Port> I<Port>
1523 TCP-Port to connect to. Defaults to B<11211>.
1527 =head2 Plugin C<mysql>
1529 The C<mysql plugin> requires B<mysqlclient> to be installed. It connects to
1530 one or more databases when started and keeps the connection up as long as
1531 possible. When the connection is interrupted for whatever reason it will try
1532 to re-connect. The plugin will complaint loudly in case anything goes wrong.
1534 This plugin issues the MySQL C<SHOW STATUS> / C<SHOW GLOBAL STATUS> command
1535 and collects information about MySQL network traffic, executed statements,
1536 requests, the query cache and threads by evaluating the
1537 C<Bytes_{received,sent}>, C<Com_*>, C<Handler_*>, C<Qcache_*> and C<Threads_*>
1538 return values. Please refer to the B<MySQL reference manual>, I<5.1.6. Server
1539 Status Variables> for an explanation of these values.
1541 Optionally, master and slave statistics may be collected in a MySQL
1542 replication setup. In that case, information about the synchronization state
1543 of the nodes are collected by evaluating the C<Position> return value of the
1544 C<SHOW MASTER STATUS> command and the C<Seconds_Behind_Master>,
1545 C<Read_Master_Log_Pos> and C<Exec_Master_Log_Pos> return values of the
1546 C<SHOW SLAVE STATUS> command. See the B<MySQL reference manual>,
1547 I<12.5.5.21 SHOW MASTER STATUS Syntax> and
1548 I<12.5.5.31 SHOW SLAVE STATUS Syntax> for details.
1563 Socket "/var/run/mysql/mysqld.sock"
1565 SlaveNotifications true
1569 A B<Database> block defines one connection to a MySQL database. It accepts a
1570 single argument which specifies the name of the database. None of the other
1571 options are required. MySQL will use default values as documented in the
1572 section "mysql_real_connect()" in the B<MySQL reference manual>.
1576 =item B<Host> I<Hostname>
1578 Hostname of the database server. Defaults to B<localhost>.
1580 =item B<User> I<Username>
1582 Username to use when connecting to the database. The user does not have to be
1583 granted any privileges (which is synonym to granting the C<USAGE> privilege).
1584 Any existing MySQL user will do.
1586 =item B<Password> I<Password>
1588 Password needed to log into the database.
1590 =item B<Database> I<Database>
1592 Select this database. Defaults to I<no database> which is a perfectly reasonable
1593 option for what this plugin does.
1595 =item B<Port> I<Port>
1597 TCP-port to connect to. The port must be specified in its numeric form, but it
1598 must be passed as a string nonetheless. For example:
1602 If B<Host> is set to B<localhost> (the default), this setting has no effect.
1603 See the documentation for the C<mysql_real_connect> function for details.
1605 =item B<Socket> I<Socket>
1607 Specifies the path to the UNIX domain socket of the MySQL server. This option
1608 only has any effect, if B<Host> is set to B<localhost> (the default).
1609 Otherwise, use the B<Port> option above. See the documentation for the
1610 C<mysql_real_connect> function for details.
1612 =item B<MasterStats> I<true|false>
1614 =item B<SlaveStats> I<true|false>
1616 Enable the collection of master / slave statistics in a replication setup.
1618 =item B<SlaveNotifications> I<true|false>
1620 If enabled, the plugin sends a notification if the replication slave I/O and /
1621 or SQL threads are not running.
1625 =head2 Plugin C<netlink>
1627 The C<netlink> plugin uses a netlink socket to query the Linux kernel about
1628 statistics of various interface and routing aspects.
1632 =item B<Interface> I<Interface>
1634 =item B<VerboseInterface> I<Interface>
1636 Instruct the plugin to collect interface statistics. This is basically the same
1637 as the statistics provided by the C<interface> plugin (see above) but
1638 potentially much more detailed.
1640 When configuring with B<Interface> only the basic statistics will be collected,
1641 namely octets, packets, and errors. These statistics are collected by
1642 the C<interface> plugin, too, so using both at the same time is no benefit.
1644 When configured with B<VerboseInterface> all counters B<except> the basic ones,
1645 so that no data needs to be collected twice if you use the C<interface> plugin.
1646 This includes dropped packets, received multicast packets, collisions and a
1647 whole zoo of differentiated RX and TX errors. You can try the following command
1648 to get an idea of what awaits you:
1652 If I<Interface> is B<All>, all interfaces will be selected.
1654 =item B<QDisc> I<Interface> [I<QDisc>]
1656 =item B<Class> I<Interface> [I<Class>]
1658 =item B<Filter> I<Interface> [I<Filter>]
1660 Collect the octets and packets that pass a certain qdisc, class or filter.
1662 QDiscs and classes are identified by their type and handle (or classid).
1663 Filters don't necessarily have a handle, therefore the parent's handle is used.
1664 The notation used in collectd differs from that used in tc(1) in that it
1665 doesn't skip the major or minor number if it's zero and doesn't print special
1666 ids by their name. So, for example, a qdisc may be identified by
1667 C<pfifo_fast-1:0> even though the minor number of B<all> qdiscs is zero and
1668 thus not displayed by tc(1).
1670 If B<QDisc>, B<Class>, or B<Filter> is given without the second argument,
1671 i.E<nbsp>.e. without an identifier, all qdiscs, classes, or filters that are
1672 associated with that interface will be collected.
1674 Since a filter itself doesn't necessarily have a handle, the parent's handle is
1675 used. This may lead to problems when more than one filter is attached to a
1676 qdisc or class. This isn't nice, but we don't know how this could be done any
1677 better. If you have a idea, please don't hesitate to tell us.
1679 As with the B<Interface> option you can specify B<All> as the interface,
1680 meaning all interfaces.
1682 Here are some examples to help you understand the above text more easily:
1685 VerboseInterface "All"
1686 QDisc "eth0" "pfifo_fast-1:0"
1688 Class "ppp0" "htb-1:10"
1689 Filter "ppp0" "u32-1:0"
1692 =item B<IgnoreSelected>
1694 The behaviour is the same as with all other similar plugins: If nothing is
1695 selected at all, everything is collected. If some things are selected using the
1696 options described above, only these statistics are collected. If you set
1697 B<IgnoreSelected> to B<true>, this behavior is inverted, i.E<nbsp>e. the
1698 specified statistics will not be collected.
1702 =head2 Plugin C<network>
1704 The Network plugin sends data to a remote instance of collectd, receives data
1705 from a remote instance, or both at the same time. Data which has been received
1706 from the network is usually not transmitted again, but this can be actived, see
1707 the B<Forward> option below.
1709 The default IPv6 multicast group is C<ff18::efc0:4a42>. The default IPv4
1710 multicast group is C<239.192.74.66>. The default I<UDP> port is B<25826>.
1712 Both, B<Server> and B<Listen> can be used as single option or as block. When
1713 used as block, given options are valid for this socket only. For example:
1716 Server "collectd.internal.tld"
1717 <Server "collectd.external.tld">
1718 SecurityLevel "sign"
1719 Username "myhostname"
1726 =item B<E<lt>Server> I<Host> [I<Port>]B<E<gt>>
1728 The B<Server> statement/block sets the server to send datagrams to. The
1729 statement may occur multiple times to send each datagram to multiple
1732 The argument I<Host> may be a hostname, an IPv4 address or an IPv6 address. The
1733 optional second argument specifies a port number or a service name. If not
1734 given, the default, B<25826>, is used.
1736 The following options are recognized within B<Server> blocks:
1740 =item B<SecurityLevel> B<Encrypt>|B<Sign>|B<None>
1742 Set the security you require for network communication. When the security level
1743 has been set to B<Encrypt>, data sent over the network will be encrypted using
1744 I<AES-256>. The integrity of encrypted packets is ensured using I<SHA-1>. When
1745 set to B<Sign>, transmitted data is signed using the I<HMAC-SHA-256> message
1746 authentication code. When set to B<None>, data is sent without any security.
1748 This feature is only available if the I<network> plugin was linked with
1751 =item B<Username> I<Username>
1753 Sets the username to transmit. This is used by the server to lookup the
1754 password. See B<AuthFile> below. All security levels except B<None> require
1757 This feature is only available if the I<network> plugin was linked with
1760 =item B<Password> I<Password>
1762 Sets a password (shared secret) for this socket. All security levels except
1763 B<None> require this setting.
1765 This feature is only available if the I<network> plugin was linked with
1770 =item B<E<lt>Listen> I<Host> [I<Port>]B<E<gt>>
1772 The B<Listen> statement sets the interfaces to bind to. When multiple
1773 statements are found the daemon will bind to multiple interfaces.
1775 The argument I<Host> may be a hostname, an IPv4 address or an IPv6 address. If
1776 the argument is a multicast address the daemon will join that multicast group.
1777 The optional second argument specifies a port number or a service name. If not
1778 given, the default, B<25826>, is used.
1780 The following options are recognized within C<E<lt>ListenE<gt>> blocks:
1784 =item B<SecurityLevel> B<Encrypt>|B<Sign>|B<None>
1786 Set the security you require for network communication. When the security level
1787 has been set to B<Encrypt>, only encrypted data will be accepted. The integrity
1788 of encrypted packets is ensured using I<SHA-1>. When set to B<Sign>, only
1789 signed and encrypted data is accepted. When set to B<None>, all data will be
1790 accepted. If an B<AuthFile> option was given (see below), encrypted data is
1791 decrypted if possible.
1793 This feature is only available if the I<network> plugin was linked with
1796 =item B<AuthFile> I<Filename>
1798 Sets a file in which usernames are mapped to passwords. These passwords are
1799 used to verify signatures and to decrypt encrypted network packets. If
1800 B<SecurityLevel> is set to B<None>, this is optional. If given, signed data is
1801 verified and encrypted packets are decrypted. Otherwise, signed data is
1802 accepted without checking the signature and encrypted data cannot be decrypted.
1803 For the other security levels this option is mandatory.
1805 The file format is very simple: Each line consists of a username followed by a
1806 colon and any number of spaces followed by the password. To demonstrate, an
1807 example file could look like this:
1812 Each time a packet is received, the modification time of the file is checked
1813 using L<stat(2)>. If the file has been changed, the contents is re-read. While
1814 the file is being read, it is locked using L<fcntl(2)>.
1818 =item B<TimeToLive> I<1-255>
1820 Set the time-to-live of sent packets. This applies to all, unicast and
1821 multicast, and IPv4 and IPv6 packets. The default is to not change this value.
1822 That means that multicast packets will be sent with a TTL of C<1> (one) on most
1825 =item B<Forward> I<true|false>
1827 If set to I<true>, write packets that were received via the network plugin to
1828 the sending sockets. This should only be activated when the B<Listen>- and
1829 B<Server>-statements differ. Otherwise packets may be send multiple times to
1830 the same multicast group. While this results in more network traffic than
1831 necessary it's not a huge problem since the plugin has a duplicate detection,
1832 so the values will not loop.
1834 =item B<CacheFlush> I<Seconds>
1836 For each host/plugin/type combination the C<network plugin> caches the time of
1837 the last value being sent or received. Every I<Seconds> seconds the plugin
1838 searches and removes all entries that are older than I<Seconds> seconds, thus
1839 freeing the unused memory again. Since this process is somewhat expensive and
1840 normally doesn't do much, this value should not be too small. The default is
1841 1800 seconds, but setting this to 86400 seconds (one day) will not do much harm
1846 =head2 Plugin C<nginx>
1848 This plugin collects the number of connections and requests handled by the
1849 C<nginx daemon> (speak: engineE<nbsp>X), a HTTP and mail server/proxy. It
1850 queries the page provided by the C<ngx_http_stub_status_module> module, which
1851 isn't compiled by default. Please refer to
1852 L<http://wiki.codemongers.com/NginxStubStatusModule> for more information on
1853 how to compile and configure nginx and this module.
1855 The following options are accepted by the C<nginx plugin>:
1859 =item B<URL> I<http://host/nginx_status>
1861 Sets the URL of the C<ngx_http_stub_status_module> output.
1863 =item B<User> I<Username>
1865 Optional user name needed for authentication.
1867 =item B<Password> I<Password>
1869 Optional password needed for authentication.
1871 =item B<VerifyPeer> B<true|false>
1873 Enable or disable peer SSL certificate verification. See
1874 L<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by default.
1876 =item B<VerifyHost> B<true|false>
1878 Enable or disable peer host name verification. If enabled, the plugin checks
1879 if the C<Common Name> or a C<Subject Alternate Name> field of the SSL
1880 certificate matches the host name provided by the B<URL> option. If this
1881 identity check fails, the connection is aborted. Obviously, only works when
1882 connecting to a SSL enabled server. Enabled by default.
1884 =item B<CACert> I<File>
1886 File that holds one or more SSL certificates. If you want to use HTTPS you will
1887 possibly need this option. What CA certificates come bundled with C<libcurl>
1888 and are checked by default depends on the distribution you use.
1892 =head2 Plugin C<notify_desktop>
1894 This plugin sends a desktop notification to a notification daemon, as defined
1895 in the Desktop Notification Specification. To actually display the
1896 notifications, B<notification-daemon> is required and B<collectd> has to be
1897 able to access the X server.
1899 The Desktop Notification Specification can be found at
1900 L<http://www.galago-project.org/specs/notification/>.
1904 =item B<OkayTimeout> I<timeout>
1906 =item B<WarningTimeout> I<timeout>
1908 =item B<FailureTimeout> I<timeout>
1910 Set the I<timeout>, in milliseconds, after which to expire the notification
1911 for C<OKAY>, C<WARNING> and C<FAILURE> severities respectively. If zero has
1912 been specified, the displayed notification will not be closed at all - the
1913 user has to do so herself. These options default to 5000. If a negative number
1914 has been specified, the default is used as well.
1918 =head2 Plugin C<notify_email>
1920 The I<notify_email> plugin uses the I<ESMTP> library to send notifications to a
1921 configured email address.
1923 I<libESMTP> is available from L<http://www.stafford.uklinux.net/libesmtp/>.
1925 Available configuration options:
1929 =item B<From> I<Address>
1931 Email address from which the emails should appear to come from.
1933 Default: C<root@localhost>
1935 =item B<Recipient> I<Address>
1937 Configures the email address(es) to which the notifications should be mailed.
1938 May be repeated to send notifications to multiple addresses.
1940 At least one B<Recipient> must be present for the plugin to work correctly.
1942 =item B<SMTPServer> I<Hostname>
1944 Hostname of the SMTP server to connect to.
1946 Default: C<localhost>
1948 =item B<SMTPPort> I<Port>
1950 TCP port to connect to.
1954 =item B<SMTPUser> I<Username>
1956 Username for ASMTP authentication. Optional.
1958 =item B<SMTPPassword> I<Password>
1960 Password for ASMTP authentication. Optional.
1962 =item B<Subject> I<Subject>
1964 Subject-template to use when sending emails. There must be exactly two
1965 string-placeholders in the subject, given in the standard I<printf(3)> syntax,
1966 i.E<nbsp>e. C<%s>. The first will be replaced with the severity, the second
1969 Default: C<Collectd notify: %s@%s>
1973 =head2 Plugin C<ntpd>
1977 =item B<Host> I<Hostname>
1979 Hostname of the host running B<ntpd>. Defaults to B<localhost>.
1981 =item B<Port> I<Port>
1983 UDP-Port to connect to. Defaults to B<123>.
1985 =item B<ReverseLookups> B<true>|B<false>
1987 Sets wether or not to perform reverse lookups on peers. Since the name or
1988 IP-address may be used in a filename it is recommended to disable reverse
1989 lookups. The default is to do reverse lookups to preserve backwards
1990 compatibility, though.
1994 =head2 Plugin C<nut>
1998 =item B<UPS> I<upsname>B<@>I<hostname>[B<:>I<port>]
2000 Add a UPS to collect data from. The format is identical to the one accepted by
2005 =head2 Plugin C<olsrd>
2007 The I<olsrd> plugin connects to the TCP port opened by the I<txtinfo> plugin of
2008 the Optimized Link State Routing daemon and reads information about the current
2009 state of the meshed network.
2011 The following configuration options are understood:
2015 =item B<Host> I<Host>
2017 Connect to I<Host>. Defaults to B<"localhost">.
2019 =item B<Port> I<Port>
2021 Specifies the port to connect to. This must be a string, even if you give the
2022 port as a number rather than a service name. Defaults to B<"2006">.
2024 =item B<CollectLinks> B<No>|B<Summary>|B<Detail>
2026 Specifies what information to collect about links, i.E<nbsp>e. direct
2027 connections of the daemon queried. If set to B<No>, no information is
2028 collected. If set to B<Summary>, the number of links and the average of all
2029 I<link quality> (LQ) and I<neighbor link quality> (NLQ) values is calculated.
2030 If set to B<Detail> LQ and NLQ are collected per link.
2032 Defaults to B<Detail>.
2034 =item B<CollectRoutes> B<No>|B<Summary>|B<Detail>
2036 Specifies what information to collect about routes of the daemon queried. If
2037 set to B<No>, no information is collected. If set to B<Summary>, the number of
2038 routes and the average I<metric> and I<ETX> is calculated. If set to B<Detail>
2039 metric and ETX are collected per route.
2041 Defaults to B<Summary>.
2043 =item B<CollectTopology> B<No>|B<Summary>|B<Detail>
2045 Specifies what information to collect about the global topology. If set to
2046 B<No>, no information is collected. If set to B<Summary>, the number of links
2047 in the entire topology and the average I<link quality> (LQ) is calculated.
2048 If set to B<Detail> LQ and NLQ are collected for each link in the entire topology.
2050 Defaults to B<Summary>.
2054 =head2 Plugin C<onewire>
2056 B<EXPERIMENTAL!> See notes below.
2058 The C<onewire> plugin uses the B<owcapi> library from the B<owfs> project
2059 L<http://owfs.org/> to read sensors connected via the onewire bus.
2061 Currently only temperature sensors (sensors with the family code C<10>,
2062 e.E<nbsp>g. DS1820, DS18S20, DS1920) can be read. If you have other sensors you
2063 would like to have included, please send a sort request to the mailing list.
2065 Hubs (the DS2409 chips) are working, but read the note, why this plugin is
2066 experimental, below.
2070 =item B<Device> I<Device>
2072 Sets the device to read the values from. This can either be a "real" hardware
2073 device, such as a serial port or an USB port, or the address of the
2074 L<owserver(1)> socket, usually B<localhost:4304>.
2076 Though the documentation claims to automatically recognize the given address
2077 format, with versionE<nbsp>2.7p4 we had to specify the type explicitly. So
2078 with that version, the following configuration worked for us:
2081 Device "-s localhost:4304"
2084 This directive is B<required> and does not have a default value.
2086 =item B<Sensor> I<Sensor>
2088 Selects sensors to collect or to ignore, depending on B<IgnoreSelected>, see
2089 below. Sensors are specified without the family byte at the beginning, to you'd
2090 use C<F10FCA000800>, and B<not> include the leading C<10.> family byte and
2093 =item B<IgnoreSelected> I<true>|I<false>
2095 If no configuration if given, the B<onewire> plugin will collect data from all
2096 sensors found. This may not be practical, especially if sensors are added and
2097 removed regularly. Sometimes, however, it's easier/preferred to collect only
2098 specific sensors or all sensors I<except> a few specified ones. This option
2099 enables you to do that: By setting B<IgnoreSelected> to I<true> the effect of
2100 B<Sensor> is inverted: All selected interfaces are ignored and all other
2101 interfaces are collected.
2103 =item B<Interval> I<Seconds>
2105 Sets the interval in which all sensors should be read. If not specified, the
2106 global B<Interval> setting is used.
2110 B<EXPERIMENTAL!> The C<onewire> plugin is experimental, because it doesn't yet
2111 work with big setups. It works with one sensor being attached to one
2112 controller, but as soon as you throw in a couple more senors and maybe a hub
2113 or two, reading all values will take more than ten seconds (the default
2114 interval). We will probably add some separate thread for reading the sensors
2115 and some cache or something like that, but it's not done yet. We will try to
2116 maintain backwards compatibility in the future, but we can't promise. So in
2117 short: If it works for you: Great! But keep in mind that the config I<might>
2118 change, though this is unlikely. Oh, and if you want to help improving this
2119 plugin, just send a short notice to the mailing list. ThanksE<nbsp>:)
2121 =head2 Plugin C<openvpn>
2123 The OpenVPN plugin reads a status file maintained by OpenVPN and gathers
2124 traffic statistics about connected clients.
2126 To set up OpenVPN to write to the status file periodically, use the
2127 B<--status> option of OpenVPN. Since OpenVPN can write two different formats,
2128 you need to set the required format, too. This is done by setting
2129 B<--status-version> to B<2>.
2131 So, in a nutshell you need:
2133 openvpn $OTHER_OPTIONS \
2134 --status "/var/run/openvpn-status" 10 \
2141 =item B<StatusFile> I<File>
2143 Specifies the location of the status file.
2147 =head2 Plugin C<oracle>
2149 The "oracle" plugin uses the Oracle® Call Interface I<(OCI)> to connect to an
2150 Oracle® Database and lets you execute SQL statements there. It is very similar
2151 to the "dbi" plugin, because it was written around the same time. See the "dbi"
2152 plugin's documentation above for details.
2155 <Query "out_of_stock">
2156 Statement "SELECT category, COUNT(*) AS value FROM products WHERE in_stock = 0 GROUP BY category"
2159 # InstancePrefix "foo"
2160 InstancesFrom "category"
2164 <Database "product_information">
2168 Query "out_of_stock"
2172 =head3 B<Query> blocks
2174 The Query blocks are handled identically to the Query blocks of the "dbi"
2175 plugin. Please see its documentation above for details on how to specify
2178 =head3 B<Database> blocks
2180 Database blocks define a connection to a database and which queries should be
2181 sent to that database. Each database needs a "name" as string argument in the
2182 starting tag of the block. This name will be used as "PluginInstance" in the
2183 values submitted to the daemon. Other than that, that name is not used.
2187 =item B<ConnectID> I<ID>
2189 Defines the "database alias" or "service name" to connect to. Usually, these
2190 names are defined in the file named C<$ORACLE_HOME/network/admin/tnsnames.ora>.
2192 =item B<Username> I<Username>
2194 Username used for authentication.
2196 =item B<Password> I<Password>
2198 Password used for authentication.
2200 =item B<Query> I<QueryName>
2202 Associates the query named I<QueryName> with this database connection. The
2203 query needs to be defined I<before> this statement, i.E<nbsp>e. all query
2204 blocks you want to refer to must be placed above the database block you want to
2209 =head2 Plugin C<perl>
2211 This plugin embeds a Perl-interpreter into collectd and provides an interface
2212 to collectd's plugin system. See L<collectd-perl(5)> for its documentation.
2214 =head2 Plugin C<ping>
2216 The I<Ping> plugin starts a new thread which sends ICMP "ping" packets to the
2217 configured hosts periodically and measures the network latency. Whenever the
2218 C<read> function of the plugin is called, it submits the average latency, the
2219 standard deviation and the drop rate for each host.
2221 Available configuration options:
2225 =item B<Host> I<IP-address>
2227 Host to ping periodically. This option may be repeated several times to ping
2230 =item B<Interval> I<Seconds>
2232 Sets the interval in which to send ICMP echo packets to the configured hosts.
2233 This is B<not> the interval in which statistics are queries from the plugin but
2234 the interval in which the hosts are "pinged". Therefore, the setting here
2235 should be smaller than or equal to the global B<Interval> setting. Fractional
2236 times, such as "1.24" are allowed.
2240 =item B<Timeout> I<Seconds>
2242 Time to wait for a response from the host to which an ICMP packet had been
2243 sent. If a reply was not received after I<Seconds> seconds, the host is assumed
2244 to be down or the packet to be dropped. This setting must be smaller than the
2245 B<Interval> setting above for the plugin to work correctly. Fractional
2246 arguments are accepted.
2250 =item B<TTL> I<0-255>
2252 Sets the Time-To-Live of generated ICMP packets.
2256 =head2 Plugin C<postgresql>
2258 The C<postgresql> plugin queries statistics from PostgreSQL databases. It
2259 keeps a persistent connection to all configured databases and tries to
2260 reconnect if the connection has been interrupted. A database is configured by
2261 specifying a B<Database> block as described below. The default statistics are
2262 collected from PostgreSQL's B<statistics collector> which thus has to be
2263 enabled for this plugin to work correctly. This should usually be the case by
2264 default. See the section "The Statistics Collector" of the B<PostgreSQL
2265 Documentation> for details.
2267 By specifying custom database queries using a B<Query> block as described
2268 below, you may collect any data that is available from some PostgreSQL
2269 database. This way, you are able to access statistics of external daemons
2270 which are available in a PostgreSQL database or use future or special
2271 statistics provided by PostgreSQL without the need to upgrade your collectd
2274 The B<PostgreSQL Documentation> manual can be found at
2275 L<http://www.postgresql.org/docs/manuals/>.
2279 Statement "SELECT magic FROM wizard WHERE host = $1;"
2283 InstancePrefix "magic"
2288 <Query rt36_tickets>
2289 Statement "SELECT COUNT(type) AS count, type \
2291 WHEN resolved = 'epoch' THEN 'open' \
2292 ELSE 'resolved' END AS type \
2293 FROM tickets) type \
2297 InstancePrefix "rt36_tickets"
2298 InstancesFrom "type"
2309 KRBSrvName "kerberos_service_name"
2314 Service "service_name"
2315 Query backend # predefined
2320 The B<Query> block defines one database query which may later be used by a
2321 database definition. It accepts a single mandatory argument which specifies
2322 the name of the query. The names of all queries have to be unique (see the
2323 B<MinPGVersion> and B<MaxPGVersion> options below for an exception to this
2324 rule). The following configuration options are available to define the query:
2326 In each B<Query> block, there is one or more B<Result> blocks. B<Result>
2327 blocks define how to handle the values returned from the query. They define
2328 which column holds which value and how to dispatch that value to the daemon.
2329 Multiple B<Result> blocks may be used to extract multiple values from a single
2334 =item B<Statement> I<sql query statement>
2336 Specify the I<sql query statement> which the plugin should execute. The string
2337 may contain the tokens B<$1>, B<$2>, etc. which are used to reference the
2338 first, second, etc. parameter. The value of the parameters is specified by the
2339 B<Param> configuration option - see below for details. To include a literal
2340 B<$> character followed by a number, surround it with single quotes (B<'>).
2342 Any SQL command which may return data (such as C<SELECT> or C<SHOW>) is
2343 allowed. Note, however, that only a single command may be used. Semicolons are
2344 allowed as long as a single non-empty command has been specified only.
2346 The returned lines will be handled separately one after another.
2348 =item B<Query> I<sql query statement>
2350 This is a deprecated synonym for B<Statement>. It will be removed in version 5
2353 =item B<Param> I<hostname>|I<database>|I<username>|I<interval>
2355 Specify the parameters which should be passed to the SQL query. The parameters
2356 are referred to in the SQL query as B<$1>, B<$2>, etc. in the same order as
2357 they appear in the configuration file. The value of the parameter is
2358 determined depending on the value of the B<Param> option as follows:
2364 The configured hostname of the database connection. If a UNIX domain socket is
2365 used, the parameter expands to "localhost".
2369 The name of the database of the current connection.
2373 The username used to connect to the database.
2377 The interval collectd is using (as specified by the B<Interval> option).
2381 Please note that parameters are only supported by PostgreSQL's protocol
2382 version 3 and above which was introduced in version 7.4 of PostgreSQL.
2384 =item B<Type> I<type>
2386 The I<type> name to be used when dispatching the values. The type describes
2387 how to handle the data and where to store it. See L<types.db(5)> for more
2388 details on types and their configuration. The number and type of values (as
2389 selected by the B<ValuesFrom> option) has to match the type of the given name.
2391 This option is required inside a B<Result> block.
2393 =item B<InstancePrefix> I<prefix>
2395 =item B<InstancesFrom> I<column0> [I<column1> ...]
2397 Specify how to create the "TypeInstance" for each data set (i.E<nbsp>e. line).
2398 B<InstancePrefix> defines a static prefix that will be prepended to all type
2399 instances. B<InstancesFrom> defines the column names whose values will be used
2400 to create the type instance. Multiple values will be joined together using the
2401 hyphen (C<->) as separation character.
2403 The plugin itself does not check whether or not all built instances are
2404 different. It is your responsibility to assure that each is unique.
2406 Both options are optional. If none is specified, the type instance will be
2409 =item B<ValuesFrom> I<column0> [I<column1> ...]
2411 Names the columns whose content is used as the actual data for the data sets
2412 that are dispatched to the daemon. How many such columns you need is
2413 determined by the B<Type> setting as explained above. If you specify too many
2414 or not enough columns, the plugin will complain about that and no data will be
2415 submitted to the daemon.
2417 The actual data type, as seen by PostgreSQL, is not that important as long as
2418 it represents numbers. The plugin will automatically cast the values to the
2419 right type if it know how to do that. For that, it uses the L<strtoll(3)> and
2420 L<strtod(3)> functions, so anything supported by those functions is supported
2421 by the plugin as well.
2423 This option is required inside a B<Result> block and may be specified multiple
2424 times. If multiple B<ValuesFrom> options are specified, the columns are read
2427 =item B<Column> I<type> [I<type instance>]
2429 This is a deprecated alternative to a B<Result> block. It will be removed in
2430 version 5 of collectd. It is equivalent to the following B<Result> block:
2434 InstancePrefix I<type instance>
2435 ValuesFrom I<name of the x. column>
2438 The order of the B<Column> options defines which columns of the query result
2439 should be used. The first option specifies the data found in the first column,
2440 the second option that of the second column, and so on.
2442 =item B<MinPGVersion> I<version>
2444 =item B<MaxPGVersion> I<version>
2446 Specify the minimum or maximum version of PostgreSQL that this query should be
2447 used with. Some statistics might only be available with certain versions of
2448 PostgreSQL. This allows you to specify multiple queries with the same name but
2449 which apply to different versions, thus allowing you to use the same
2450 configuration in a heterogeneous environment.
2452 The I<version> has to be specified as the concatenation of the major, minor
2453 and patch-level versions, each represented as two-decimal-digit numbers. For
2454 example, version 8.2.3 will become 80203.
2458 The following predefined queries are available (the definitions can be found
2459 in the F<postgresql_default.conf> file which, by default, is available at
2460 C<I<prefix>/share/collectd/>):
2466 This query collects the number of backends, i.E<nbsp>e. the number of
2469 =item B<transactions>
2471 This query collects the numbers of committed and rolled-back transactions of
2476 This query collects the numbers of various table modifications (i.E<nbsp>e.
2477 insertions, updates, deletions) of the user tables.
2479 =item B<query_plans>
2481 This query collects the numbers of various table scans and returned tuples of
2484 =item B<table_states>
2486 This query collects the numbers of live and dead rows in the user tables.
2490 This query collects disk block access counts for user tables.
2494 This query collects the on-disk size of the database in bytes.
2498 The B<Database> block defines one PostgreSQL database for which to collect
2499 statistics. It accepts a single mandatory argument which specifies the
2500 database name. None of the other options are required. PostgreSQL will use
2501 default values as documented in the section "CONNECTING TO A DATABASE" in the
2502 L<psql(1)> manpage. However, be aware that those defaults may be influenced by
2503 the user collectd is run as and special environment variables. See the manpage
2508 =item B<Host> I<hostname>
2510 Specify the hostname or IP of the PostgreSQL server to connect to. If the
2511 value begins with a slash, it is interpreted as the directory name in which to
2512 look for the UNIX domain socket.
2514 This option is also used to determine the hostname that is associated with a
2515 collected data set. If it has been omitted or either begins with with a slash
2516 or equals B<localhost> it will be replaced with the global hostname definition
2517 of collectd. Any other value will be passed literally to collectd when
2518 dispatching values. Also see the global B<Hostname> and B<FQDNLookup> options.
2520 =item B<Port> I<port>
2522 Specify the TCP port or the local UNIX domain socket file extension of the
2525 =item B<User> I<username>
2527 Specify the username to be used when connecting to the server.
2529 =item B<Password> I<password>
2531 Specify the password to be used when connecting to the server.
2533 =item B<SSLMode> I<disable>|I<allow>|I<prefer>|I<require>
2535 Specify whether to use an SSL connection when contacting the server. The
2536 following modes are supported:
2542 Do not use SSL at all.
2546 First, try to connect without using SSL. If that fails, try using SSL.
2548 =item I<prefer> (default)
2550 First, try to connect using SSL. If that fails, try without using SSL.
2558 =item B<KRBSrvName> I<kerberos_service_name>
2560 Specify the Kerberos service name to use when authenticating with Kerberos 5
2561 or GSSAPI. See the sections "Kerberos authentication" and "GSSAPI" of the
2562 B<PostgreSQL Documentation> for details.
2564 =item B<Service> I<service_name>
2566 Specify the PostgreSQL service name to use for additional parameters. That
2567 service has to be defined in F<pg_service.conf> and holds additional
2568 connection parameters. See the section "The Connection Service File" in the
2569 B<PostgreSQL Documentation> for details.
2571 =item B<Query> I<query>
2573 Specify a I<query> which should be executed for the database connection. This
2574 may be any of the predefined or user-defined queries. If no such option is
2575 given, it defaults to "backends", "transactions", "queries", "query_plans",
2576 "table_states", "disk_io" and "disk_usage". Else, the specified queries are
2581 =head2 Plugin C<powerdns>
2583 The C<powerdns> plugin queries statistics from an authoritative PowerDNS
2584 nameserver and/or a PowerDNS recursor. Since both offer a wide variety of
2585 values, many of which are probably meaningless to most users, but may be useful
2586 for some. So you may chose which values to collect, but if you don't, some
2587 reasonable defaults will be collected.
2590 <Server "server_name">
2592 Collect "udp-answers" "udp-queries"
2593 Socket "/var/run/pdns.controlsocket"
2595 <Recursor "recursor_name">
2597 Collect "cache-hits" "cache-misses"
2598 Socket "/var/run/pdns_recursor.controlsocket"
2600 LocalSocket "/opt/collectd/var/run/collectd-powerdns"
2605 =item B<Server> and B<Recursor> block
2607 The B<Server> block defines one authoritative server to query, the B<Recursor>
2608 does the same for an recursing server. The possible options in both blocks are
2609 the same, though. The argument defines a name for the serverE<nbsp>/ recursor
2614 =item B<Collect> I<Field>
2616 Using the B<Collect> statement you can select which values to collect. Here,
2617 you specify the name of the values as used by the PowerDNS servers, e.E<nbsp>g.
2618 C<dlg-only-drops>, C<answers10-100>.
2620 The method of getting the values differs for B<Server> and B<Recursor> blocks:
2621 When querying the server a C<SHOW *> command is issued in any case, because
2622 that's the only way of getting multiple values out of the server at once.
2623 collectd then picks out the values you have selected. When querying the
2624 recursor, a command is generated to query exactly these values. So if you
2625 specify invalid fields when querying the recursor, a syntax error may be
2626 returned by the daemon and collectd may not collect any values at all.
2628 If no B<Collect> statement is given, the following B<Server> values will be
2635 =item packetcache-hit
2637 =item packetcache-miss
2639 =item packetcache-size
2641 =item query-cache-hit
2643 =item query-cache-miss
2645 =item recursing-answers
2647 =item recursing-questions
2659 The following B<Recursor> values will be collected by default:
2663 =item noerror-answers
2665 =item nxdomain-answers
2667 =item servfail-answers
2685 Please note that up to that point collectd doesn't know what values are
2686 available on the server and values that are added do not need a change of the
2687 mechanism so far. However, the values must be mapped to collectd's naming
2688 scheme, which is done using a lookup table that lists all known values. If
2689 values are added in the future and collectd does not know about them, you will
2690 get an error much like this:
2692 powerdns plugin: submit: Not found in lookup table: foobar = 42
2694 In this case please file a bug report with the collectd team.
2696 =item B<Socket> I<Path>
2698 Configures the path to the UNIX domain socket to be used when connecting to the
2699 daemon. By default C<${localstatedir}/run/pdns.controlsocket> will be used for
2700 an authoritative server and C<${localstatedir}/run/pdns_recursor.controlsocket>
2701 will be used for the recursor.
2705 =item B<LocalSocket> I<Path>
2707 Querying the recursor is done using UDP. When using UDP over UNIX domain
2708 sockets, the client socket needs a name in the file system, too. You can set
2709 this local name to I<Path> using the B<LocalSocket> option. The default is
2710 C<I<prefix>/var/run/collectd-powerdns>.
2714 =head2 Plugin C<processes>
2718 =item B<Process> I<Name>
2720 Select more detailed statistics of processes matching this name. The statistics
2721 collected for these selected processes are size of the resident segment size
2722 (RSS), user- and system-time used, number of processes and number of threads,
2723 and minor and major pagefaults.
2725 =item B<ProcessMatch> I<name> I<regex>
2727 Similar to the B<Process> option this allows to select more detailed
2728 statistics of processes matching the specified I<regex> (see L<regex(7)> for
2729 details). The statistics of all matching processes are summed up and
2730 dispatched to the daemon using the specified I<name> as an identifier. This
2731 allows to "group" several processes together. I<name> must not contain
2736 =head2 Plugin C<protocols>
2738 Collects a lot of information about various network protocols, such as I<IP>,
2739 I<TCP>, I<UDP>, etc.
2741 Available configuration options:
2745 =item B<Value> I<Selector>
2747 Selects whether or not to select a specific value. The string being matched is
2748 of the form "I<Protocol>:I<ValueName>", where I<Protocol> will be used as the
2749 plugin instance and I<ValueName> will be used as type instance. An example of
2750 the string being used would be C<Tcp:RetransSegs>.
2752 You can use regular expressions to match a large number of values with just one
2753 configuration option. To select all "extended" I<TCP> values, you could use the
2754 following statement:
2758 Whether only matched values are selected or all matched values are ignored
2759 depends on the B<IgnoreSelected>. By default, only matched values are selected.
2760 If no value is configured at all, all values will be selected.
2762 =item B<IgnoreSelected> B<true>|B<false>
2764 If set to B<true>, inverts the selection made by B<Value>, i.E<nbsp>e. all
2765 matching values will be ignored.
2769 =head2 Plugin C<rrdcached>
2771 The C<rrdcached> plugin uses the RRDTool accelerator daemon, L<rrdcached(1)>,
2772 to store values to RRD files in an efficient manner. The combination of the
2773 C<rrdcached> B<plugin> and the C<rrdcached> B<daemon> is very similar to the
2774 way the C<rrdtool> plugin works (see below). The added abstraction layer
2775 provides a number of benefits, though: Because the cache is not within
2776 C<collectd> anymore, it does not need to be flushed when C<collectd> is to be
2777 restarted. This results in much shorter (if any) gaps in graphs, especially
2778 under heavy load. Also, the C<rrdtool> command line utility is aware of the
2779 daemon so that it can flush values to disk automatically when needed. This
2780 allows to integrate automated flushing of values into graphing solutions much
2783 There are disadvantages, though: The daemon may reside on a different host, so
2784 it may not be possible for C<collectd> to create the appropriate RRD files
2785 anymore. And even if C<rrdcached> runs on the same host, it may run in a
2786 different base directory, so relative paths may do weird stuff if you're not
2789 So the B<recommended configuration> is to let C<collectd> and C<rrdcached> run
2790 on the same host, communicating via a UNIX domain socket. The B<DataDir>
2791 setting should be set to an absolute path, so that a changed base directory
2792 does not result in RRD files being createdE<nbsp>/ expected in the wrong place.
2796 =item B<DaemonAddress> I<Address>
2798 Address of the daemon as understood by the C<rrdc_connect> function of the RRD
2799 library. See L<rrdcached(1)> for details. Example:
2801 <Plugin "rrdcached">
2802 DaemonAddress "unix:/var/run/rrdcached.sock"
2805 =item B<DataDir> I<Directory>
2807 Set the base directory in which the RRD files reside. If this is a relative
2808 path, it is relative to the working base directory of the C<rrdcached> daemon!
2809 Use of an absolute path is recommended.
2811 =item B<CreateFiles> B<true>|B<false>
2813 Enables or disables the creation of RRD files. If the daemon is not running
2814 locally, or B<DataDir> is set to a relative path, this will not work as
2815 expected. Default is B<true>.
2819 =head2 Plugin C<rrdtool>
2821 You can use the settings B<StepSize>, B<HeartBeat>, B<RRARows>, and B<XFF> to
2822 fine-tune your RRD-files. Please read L<rrdcreate(1)> if you encounter problems
2823 using these settings. If you don't want to dive into the depths of RRDTool, you
2824 can safely ignore these settings.
2828 =item B<DataDir> I<Directory>
2830 Set the directory to store RRD-files under. Per default RRD-files are generated
2831 beneath the daemon's working directory, i.E<nbsp>e. the B<BaseDir>.
2833 =item B<StepSize> I<Seconds>
2835 B<Force> the stepsize of newly created RRD-files. Ideally (and per default)
2836 this setting is unset and the stepsize is set to the interval in which the data
2837 is collected. Do not use this option unless you absolutely have to for some
2838 reason. Setting this option may cause problems with the C<snmp plugin>, the
2839 C<exec plugin> or when the daemon is set up to receive data from other hosts.
2841 =item B<HeartBeat> I<Seconds>
2843 B<Force> the heartbeat of newly created RRD-files. This setting should be unset
2844 in which case the heartbeat is set to twice the B<StepSize> which should equal
2845 the interval in which data is collected. Do not set this option unless you have
2846 a very good reason to do so.
2848 =item B<RRARows> I<NumRows>
2850 The C<rrdtool plugin> calculates the number of PDPs per CDP based on the
2851 B<StepSize>, this setting and a timespan. This plugin creates RRD-files with
2852 three times five RRAs, i. e. five RRAs with the CFs B<MIN>, B<AVERAGE>, and
2853 B<MAX>. The five RRAs are optimized for graphs covering one hour, one day, one
2854 week, one month, and one year.
2856 So for each timespan, it calculates how many PDPs need to be consolidated into
2857 one CDP by calculating:
2858 number of PDPs = timespan / (stepsize * rrarows)
2860 Bottom line is, set this no smaller than the width of you graphs in pixels. The
2863 =item B<RRATimespan> I<Seconds>
2865 Adds an RRA-timespan, given in seconds. Use this option multiple times to have
2866 more then one RRA. If this option is never used, the built-in default of (3600,
2867 86400, 604800, 2678400, 31622400) is used.
2869 For more information on how RRA-sizes are calculated see B<RRARows> above.
2871 =item B<XFF> I<Factor>
2873 Set the "XFiles Factor". The default is 0.1. If unsure, don't set this option.
2875 =item B<CacheFlush> I<Seconds>
2877 When the C<rrdtool> plugin uses a cache (by setting B<CacheTimeout>, see below)
2878 it writes all values for a certain RRD-file if the oldest value is older than
2879 (or equal to) the number of seconds specified. If some RRD-file is not updated
2880 anymore for some reason (the computer was shut down, the network is broken,
2881 etc.) some values may still be in the cache. If B<CacheFlush> is set, then the
2882 entire cache is searched for entries older than B<CacheTimeout> seconds and
2883 written to disk every I<Seconds> seconds. Since this is kind of expensive and
2884 does nothing under normal circumstances, this value should not be too small.
2885 900 seconds might be a good value, though setting this to 7200 seconds doesn't
2886 normally do much harm either.
2888 =item B<CacheTimeout> I<Seconds>
2890 If this option is set to a value greater than zero, the C<rrdtool plugin> will
2891 save values in a cache, as described above. Writing multiple values at once
2892 reduces IO-operations and thus lessens the load produced by updating the files.
2893 The trade off is that the graphs kind of "drag behind" and that more memory is
2896 =item B<WritesPerSecond> I<Updates>
2898 When collecting many statistics with collectd and the C<rrdtool> plugin, you
2899 will run serious performance problems. The B<CacheFlush> setting and the
2900 internal update queue assert that collectd continues to work just fine even
2901 under heavy load, but the system may become very unresponsive and slow. This is
2902 a problem especially if you create graphs from the RRD files on the same
2903 machine, for example using the C<graph.cgi> script included in the
2904 C<contrib/collection3/> directory.
2906 This setting is designed for very large setups. Setting this option to a value
2907 between 25 and 80 updates per second, depending on your hardware, will leave
2908 the server responsive enough to draw graphs even while all the cached values
2909 are written to disk. Flushed values, i.E<nbsp>e. values that are forced to disk
2910 by the B<FLUSH> command, are B<not> effected by this limit. They are still
2911 written as fast as possible, so that web frontends have up to date data when
2914 For example: If you have 100,000 RRD files and set B<WritesPerSecond> to 30
2915 updates per second, writing all values to disk will take approximately
2916 56E<nbsp>minutes. Together with the flushing ability that's integrated into
2917 "collection3" you'll end up with a responsive and fast system, up to date
2918 graphs and basically a "backup" of your values every hour.
2922 =head2 Plugin C<sensors>
2924 The C<sensors plugin> uses B<lm_sensors> to retrieve sensor-values. This means
2925 that all the needed modules have to be loaded and lm_sensors has to be
2926 configured (most likely by editing F</etc/sensors.conf>. Read
2927 L<sensors.conf(5)> for details.
2929 The B<lm_sensors> homepage can be found at
2930 L<http://secure.netroedge.com/~lm78/>.
2934 =item B<Sensor> I<chip-bus-address/type-feature>
2936 Selects the name of the sensor which you want to collect or ignore, depending
2937 on the B<IgnoreSelected> below. For example, the option "B<Sensor>
2938 I<it8712-isa-0290/voltage-in1>" will cause collectd to gather data for the
2939 voltage sensor I<in1> of the I<it8712> on the isa bus at the address 0290.
2941 =item B<IgnoreSelected> I<true>|I<false>
2943 If no configuration if given, the B<sensors>-plugin will collect data from all
2944 sensors. This may not be practical, especially for uninteresting sensors.
2945 Thus, you can use the B<Sensor>-option to pick the sensors you're interested
2946 in. Sometimes, however, it's easier/preferred to collect all sensors I<except> a
2947 few ones. This option enables you to do that: By setting B<IgnoreSelected> to
2948 I<true> the effect of B<Sensor> is inverted: All selected sensors are ignored
2949 and all other sensors are collected.
2953 =head2 Plugin C<snmp>
2955 Since the configuration of the C<snmp plugin> is a little more complicated than
2956 other plugins, its documentation has been moved to an own manpage,
2957 L<collectd-snmp(5)>. Please see there for details.
2959 =head2 Plugin C<syslog>
2963 =item B<LogLevel> B<debug|info|notice|warning|err>
2965 Sets the log-level. If, for example, set to B<notice>, then all events with
2966 severity B<notice>, B<warning>, or B<err> will be submitted to the
2969 Please note that B<debug> is only available if collectd has been compiled with
2974 =head2 Plugin C<table>
2976 The C<table plugin> provides generic means to parse tabular data and dispatch
2977 user specified values. Values are selected based on column numbers. For
2978 example, this plugin may be used to get values from the Linux L<proc(5)>
2979 filesystem or CSV (comma separated values) files.
2982 <Table "/proc/slabinfo">
2987 InstancePrefix "active_objs"
2993 InstancePrefix "objperslab"
3000 The configuration consists of one or more B<Table> blocks, each of which
3001 configures one file to parse. Within each B<Table> block, there are one or
3002 more B<Result> blocks, which configure which data to select and how to
3005 The following options are available inside a B<Table> block:
3009 =item B<Instance> I<instance>
3011 If specified, I<instance> is used as the plugin instance. So, in the above
3012 example, the plugin name C<table-slabinfo> would be used. If omitted, the
3013 filename of the table is used instead, with all special characters replaced
3014 with an underscore (C<_>).
3016 =item B<Separator> I<string>
3018 Any character of I<string> is interpreted as a delimiter between the different
3019 columns of the table. A sequence of two or more contiguous delimiters in the
3020 table is considered to be a single delimiter, i.E<nbsp>e. there cannot be any
3021 empty columns. The plugin uses the L<strtok_r(3)> function to parse the lines
3022 of a table - see its documentation for more details. This option is mandatory.
3024 A horizontal tab, newline and carriage return may be specified by C<\\t>,
3025 C<\\n> and C<\\r> respectively. Please note that the double backslashes are
3026 required because of collectd's config parsing.
3030 The following options are available inside a B<Result> block:
3034 =item B<Type> I<type>
3036 Sets the type used to dispatch the values to the daemon. Detailed information
3037 about types and their configuration can be found in L<types.db(5)>. This
3038 option is mandatory.
3040 =item B<InstancePrefix> I<prefix>
3042 If specified, prepend I<prefix> to the type instance. If omitted, only the
3043 B<InstancesFrom> option is considered for the type instance.
3045 =item B<InstancesFrom> I<column0> [I<column1> ...]
3047 If specified, the content of the given columns (identified by the column
3048 number starting at zero) will be used to create the type instance for each
3049 row. Multiple values (and the instance prefix) will be joined together with
3050 dashes (I<->) as separation character. If omitted, only the B<InstancePrefix>
3051 option is considered for the type instance.
3053 The plugin itself does not check whether or not all built instances are
3054 different. It’s your responsibility to assure that each is unique. This is
3055 especially true, if you do not specify B<InstancesFrom>: B<You> have to make
3056 sure that the table only contains one row.
3058 If neither B<InstancePrefix> nor B<InstancesFrom> is given, the type instance
3061 =item B<ValuesFrom> I<column0> [I<column1> ...]
3063 Specifies the columns (identified by the column numbers starting at zero)
3064 whose content is used as the actual data for the data sets that are dispatched
3065 to the daemon. How many such columns you need is determined by the B<Type>
3066 setting above. If you specify too many or not enough columns, the plugin will
3067 complain about that and no data will be submitted to the daemon. The plugin
3068 uses L<strtoll(3)> and L<strtod(3)> to parse counter and gauge values
3069 respectively, so anything supported by those functions is supported by the
3070 plugin as well. This option is mandatory.
3074 =head2 Plugin C<tail>
3076 The C<tail plugin> follows logfiles, just like L<tail(1)> does, parses
3077 each line and dispatches found values. What is matched can be configured by the
3078 user using (extended) regular expressions, as described in L<regex(7)>.
3081 <File "/var/log/exim4/mainlog">
3084 Regex "S=([1-9][0-9]*)"
3090 Regex "\\<R=local_user\\>"
3093 Instance "local_user"
3098 The config consists of one or more B<File> blocks, each of which configures one
3099 logfile to parse. Within each B<File> block, there are one or more B<Match>
3100 blocks, which configure a regular expression to search for.
3102 The B<Instance> option in the B<File> block may be used to set the plugin
3103 instance. So in the above example the plugin name C<tail-foo> would be used.
3104 This plugin instance is for all B<Match> blocks that B<follow> it, until the
3105 next B<Instance> option. This way you can extract several plugin instances from
3106 one logfile, handy when parsing syslog and the like.
3108 Each B<Match> block has the following options to describe how the match should
3113 =item B<Regex> I<regex>
3115 Sets the regular expression to use for matching against a line. The first
3116 subexpression has to match something that can be turned into a number by
3117 L<strtoll(3)> or L<strtod(3)>, depending on the value of C<CounterAdd>, see
3118 below. Because B<extended> regular expressions are used, you do not need to use
3119 backslashes for subexpressions! If in doubt, please consult L<regex(7)>. Due to
3120 collectd's config parsing you need to escape backslashes, though. So if you
3121 want to match literal parentheses you need to do the following:
3123 Regex "SPAM \\(Score: (-?[0-9]+\\.[0-9]+)\\)"
3125 =item B<DSType> I<Type>
3127 Sets how the values are cumulated. I<Type> is one of:
3131 =item B<GaugeAverage>
3133 Calculate the average.
3137 Use the smallest number only.
3141 Use the greatest number only.
3145 Use the last number found.
3149 The matched number is a counter. Simply sets the internal counter to this
3154 Add the matched value to the internal counter.
3158 Increase the internal counter by one. This B<DSType> is the only one that does
3159 not use the matched subexpression, but simply counts the number of matched
3160 lines. Thus, you may use a regular expression without submatch in this case.
3164 As you'd expect the B<Gauge*> types interpret the submatch as a floating point
3165 number, using L<strtod(3)>. The B<CounterSet> and B<CounterAdd> interpret the
3166 submatch as an integer using L<strtoll(3)>. B<CounterInc> does not use the
3167 submatch at all and it may be omitted in this case.
3169 =item B<Type> I<Type>
3171 Sets the type used to dispatch this value. Detailed information about types and
3172 their configuration can be found in L<types.db(5)>.
3174 =item B<Instance> I<TypeInstance>
3176 This optional setting sets the type instance to use.
3180 =head2 Plugin C<teamspeak2>
3182 The C<teamspeak2 plugin> connects to the query port of a teamspeak2 server and
3183 polls interesting global and virtual server data. The plugin can query only one
3184 physical server but unlimited virtual servers. You can use the following
3185 options to configure it:
3189 =item B<Host> I<hostname/ip>
3191 The hostname or ip which identifies the physical server.
3194 =item B<Port> I<port>
3196 The query port of the physical server. This needs to be a string.
3199 =item B<Server> I<port>
3201 This option has to be added once for every virtual server the plugin should
3202 query. If you want to query the virtual server on port 8767 this is what the
3203 option would look like:
3207 This option, although numeric, needs to be a string, i.E<nbsp>e. you B<must>
3208 use quotes around it! If no such statement is given only global information
3213 =head2 Plugin C<ted>
3215 The I<TED> plugin connects to a device of "The Energy Detective", a device to
3216 measure power consumption. These devices are usually connected to a serial
3217 (RS232) or USB port. The plugin opens a configured device and tries to read the
3218 current energy readings. For more information on TED, visit
3219 L<http://www.theenergydetective.com/>.
3221 Available configuration options:
3225 =item B<Device> I<Path>
3227 Path to the device on which TED is connected. collectd will need read and write
3228 permissions on that file.
3230 Default: B</dev/ttyUSB0>
3232 =item B<Retries> I<Num>
3234 Apparently reading from TED is not that reliable. You can therefore configure a
3235 number of retries here. You only configure the I<retries> here, to if you
3236 specify zero, one reading will be performed (but no retries if that fails); if
3237 you specify three, a maximum of four readings are performed. Negative values
3244 =head2 Plugin C<tcpconns>
3246 The C<tcpconns plugin> counts the number of currently established TCP
3247 connections based on the local port and/or the remote port. Since there may be
3248 a lot of connections the default if to count all connections with a local port,
3249 for which a listening socket is opened. You can use the following options to
3250 fine-tune the ports you are interested in:
3254 =item B<ListeningPorts> I<true>|I<false>
3256 If this option is set to I<true>, statistics for all local ports for which a
3257 listening socket exists are collected. The default depends on B<LocalPort> and
3258 B<RemotePort> (see below): If no port at all is specifically selected, the
3259 default is to collect listening ports. If specific ports (no matter if local or
3260 remote ports) are selected, this option defaults to I<false>, i.E<nbsp>e. only
3261 the selected ports will be collected unless this option is set to I<true>
3264 =item B<LocalPort> I<Port>
3266 Count the connections to a specific local port. This can be used to see how
3267 many connections are handled by a specific daemon, e.E<nbsp>g. the mailserver.
3268 You have to specify the port in numeric form, so for the mailserver example
3269 you'd need to set B<25>.
3271 =item B<RemotePort> I<Port>
3273 Count the connections to a specific remote port. This is useful to see how
3274 much a remote service is used. This is most useful if you want to know how many
3275 connections a local service has opened to remote services, e.E<nbsp>g. how many
3276 connections a mail server or news server has to other mail or news servers, or
3277 how many connections a web proxy holds to web servers. You have to give the
3278 port in numeric form.
3282 =head2 Plugin C<thermal>
3286 =item B<ForceUseProcfs> I<true>|I<false>
3288 By default, the C<thermal> plugin tries to read the statistics from the Linux
3289 C<sysfs> interface. If that is not available, the plugin falls back to the
3290 C<procfs> interface. By setting this option to I<true>, you can force the
3291 plugin to use the latter. This option defaults to I<false>.
3293 =item B<Device> I<Device>
3295 Selects the name of the thermal device that you want to collect or ignore,
3296 depending on the value of the B<IgnoreSelected> option. This option may be
3297 used multiple times to specify a list of devices.
3299 =item B<IgnoreSelected> I<true>|I<false>
3301 Invert the selection: If set to true, all devices B<except> the ones that
3302 match the device names specified by the B<Device> option are collected. By
3303 default only selected devices are collected if a selection is made. If no
3304 selection is configured at all, B<all> devices are selected.
3308 =head2 Plugin C<unixsock>
3312 =item B<SocketFile> I<Path>
3314 Sets the socket-file which is to be created.
3316 =item B<SocketGroup> I<Group>
3318 If running as root change the group of the UNIX-socket after it has been
3319 created. Defaults to B<collectd>.
3321 =item B<SocketPerms> I<Permissions>
3323 Change the file permissions of the UNIX-socket after it has been created. The
3324 permissions must be given as a numeric, octal value as you would pass to
3325 L<chmod(1)>. Defaults to B<0770>.
3329 =head2 Plugin C<uuid>
3331 This plugin, if loaded, causes the Hostname to be taken from the machine's
3332 UUID. The UUID is a universally unique designation for the machine, usually
3333 taken from the machine's BIOS. This is most useful if the machine is running in
3334 a virtual environment such as Xen, in which case the UUID is preserved across
3335 shutdowns and migration.
3337 The following methods are used to find the machine's UUID, in order:
3343 Check I</etc/uuid> (or I<UUIDFile>).
3347 Check for UUID from HAL (L<http://www.freedesktop.org/wiki/Software/hal>) if
3352 Check for UUID from C<dmidecode> / SMBIOS.
3356 Check for UUID from Xen hypervisor.
3360 If no UUID can be found then the hostname is not modified.
3364 =item B<UUIDFile> I<Path>
3366 Take the UUID from the given file (default I</etc/uuid>).
3370 =head2 Plugin C<vmem>
3372 The C<vmem> plugin collects information about the usage of virtual memory.
3373 Since the statistics provided by the Linux kernel are very detailed, they are
3374 collected very detailed. However, to get all the details, you have to switch
3375 them on manually. Most people just want an overview over, such as the number of
3376 pages read from swap space.
3380 =item B<Verbose> B<true>|B<false>
3382 Enables verbose collection of information. This will start collecting page
3383 "actions", e.E<nbsp>g. page allocations, (de)activations, steals and so on.
3384 Part of these statistics are collected on a "per zone" basis.
3388 =head2 Plugin C<vserver>
3390 This plugin doesn't have any options. B<VServer> support is only available for
3391 Linux. It cannot yet be found in a vanilla kernel, though. To make use of this
3392 plugin you need a kernel that has B<VServer> support built in, i.E<nbsp>e. you
3393 need to apply the patches and compile your own kernel, which will then provide
3394 the F</proc/virtual> filesystem that is required by this plugin.
3396 The B<VServer> homepage can be found at L<http://linux-vserver.org/>.
3398 B<Note>: The traffic collected by this plugin accounts for the amount of
3399 traffic passing a socket which might be a lot less than the actual on-wire
3400 traffic (e.E<nbsp>g. due to headers and retransmission). If you want to
3401 collect on-wire traffic you could, for example, use the logging facilities of
3402 iptables to feed data for the guest IPs into the iptables plugin.
3404 =head1 THRESHOLD CONFIGURATION
3406 Starting with version C<4.3.0> collectd has support for B<monitoring>. By that
3407 we mean that the values are not only stored or sent somewhere, but that they
3408 are judged and, if a problem is recognized, acted upon. The only action
3409 collectd takes itself is to generate and dispatch a "notification". Plugins can
3410 register to receive notifications and perform appropriate further actions.
3412 Since systems and what you expect them to do differ a lot, you can configure
3413 B<thresholds> for your values freely. This gives you a lot of flexibility but
3414 also a lot of responsibility.
3416 Every time a value is out of range a notification is dispatched. This means
3417 that the idle percentage of your CPU needs to be less then the configured
3418 threshold only once for a notification to be generated. There's no such thing
3419 as a moving average or similar - at least not now.
3421 Also, all values that match a threshold are considered to be relevant or
3422 "interesting". As a consequence collectd will issue a notification if they are
3423 not received for twice the last timeout of the values. If, for example, some
3424 hosts sends it's CPU statistics to the server every 60 seconds, a notification
3425 will be dispatched after about 120 seconds. It may take a little longer because
3426 the timeout is checked only once each B<Interval> on the server.
3428 When a value comes within range again or is received after it was missing, an
3429 "OKAY-notification" is dispatched.
3431 Here is a configuration example to get you started. Read below for more
3444 <Plugin "interface">
3461 WarningMin 100000000
3467 There are basically two types of configuration statements: The C<Host>,
3468 C<Plugin>, and C<Type> blocks select the value for which a threshold should be
3469 configured. The C<Plugin> and C<Type> blocks may be specified further using the
3470 C<Instance> option. You can combine the block by nesting the blocks, though
3471 they must be nested in the above order, i.E<nbsp>e. C<Host> may contain either
3472 C<Plugin> and C<Type> blocks, C<Plugin> may only contain C<Type> blocks and
3473 C<Type> may not contain other blocks. If multiple blocks apply to the same
3474 value the most specific block is used.
3476 The other statements specify the threshold to configure. They B<must> be
3477 included in a C<Type> block. Currently the following statements are recognized:
3481 =item B<FailureMax> I<Value>
3483 =item B<WarningMax> I<Value>
3485 Sets the upper bound of acceptable values. If unset defaults to positive
3486 infinity. If a value is greater than B<FailureMax> a B<FAILURE> notification
3487 will be created. If the value is greater than B<WarningMax> but less than (or
3488 equal to) B<FailureMax> a B<WARNING> notification will be created.
3490 =item B<FailureMin> I<Value>
3492 =item B<WarningMin> I<Value>
3494 Sets the lower bound of acceptable values. If unset defaults to negative
3495 infinity. If a value is less than B<FailureMin> a B<FAILURE> notification will
3496 be created. If the value is less than B<WarningMin> but greater than (or equal
3497 to) B<FailureMin> a B<WARNING> notification will be created.
3499 =item B<DataSource> I<DSName>
3501 Some data sets have more than one "data source". Interesting examples are the
3502 C<if_octets> data set, which has received (C<rx>) and sent (C<tx>) bytes and
3503 the C<disk_ops> data set, which holds C<read> and C<write> operations. The
3504 system load data set, C<load>, even has three data sources: C<shortterm>,
3505 C<midterm>, and C<longterm>.
3507 Normally, all data sources are checked against a configured threshold. If this
3508 is undesirable, or if you want to specify different limits for each data
3509 source, you can use the B<DataSource> option to have a threshold apply only to
3512 =item B<Invert> B<true>|B<false>
3514 If set to B<true> the range of acceptable values is inverted, i.E<nbsp>e.
3515 values between B<FailureMin> and B<FailureMax> (B<WarningMin> and
3516 B<WarningMax>) are not okay. Defaults to B<false>.
3518 =item B<Persist> B<true>|B<false>
3520 Sets how often notifications are generated. If set to B<true> one notification
3521 will be generated for each value that is out of the acceptable range. If set to
3522 B<false> (the default) then a notification is only generated if a value is out
3523 of range but the previous value was okay.
3525 This applies to missing values, too: If set to B<true> a notification about a
3526 missing value is generated once every B<Interval> seconds. If set to B<false>
3527 only one such notification is generated until the value appears again.
3531 =head1 FILTER CONFIGURATION
3533 Starting with collectd 4.6 there is a powerful filtering infrastructure
3534 implemented in the daemon. The concept has mostly been copied from
3535 I<ip_tables>, the packet filter infrastructure for Linux. We'll use a similar
3536 terminology, so that users that are familiar with iptables feel right at home.
3540 The following are the terms used in the remainder of the filter configuration
3541 documentation. For an ASCII-art schema of the mechanism, see
3542 L<"General structure"> below.
3548 A I<match> is a criteria to select specific values. Examples are, of course, the
3549 name of the value or it's current value.
3551 Matches are implemented in plugins which you have to load prior to using the
3552 match. The name of such plugins starts with the "match_" prefix.
3556 A I<target> is some action that is to be performed with data. Such actions
3557 could, for example, be to change part of the value's identifier or to ignore
3558 the value completely.
3560 Some of these targets are built into the daemon, see L<"Built-in targets">
3561 below. Other targets are implemented in plugins which you have to load prior to
3562 using the target. The name of such plugins starts with the "target_" prefix.
3566 The combination of any number of matches and at least one target is called a
3567 I<rule>. The target actions will be performed for all values for which B<all>
3568 matches apply. If the rule does not have any matches associated with it, the
3569 target action will be performed for all values.
3573 A I<chain> is a list of rules and possibly default targets. The rules are tried
3574 in order and if one matches, the associated target will be called. If a value
3575 is handled by a rule, it depends on the target whether or not any subsequent
3576 rules are considered or if traversal of the chain is aborted, see
3577 L<"Flow control"> below. After all rules have been checked, the default targets
3582 =head2 General structure
3584 The following shows the resulting structure:
3591 +---------+ +---------+ +---------+ +---------+
3592 ! Rule !->! Match !->! Match !->! Target !
3593 +---------+ +---------+ +---------+ +---------+
3596 +---------+ +---------+ +---------+
3597 ! Rule !->! Target !->! Target !
3598 +---------+ +---------+ +---------+
3605 +---------+ +---------+ +---------+
3606 ! Rule !->! Match !->! Target !
3607 +---------+ +---------+ +---------+
3617 There are four ways to control which way a value takes through the filter
3624 The built-in B<jump> target can be used to "call" another chain, i.E<nbsp>e.
3625 process the value with another chain. When the called chain finishes, usually
3626 the next target or rule after the jump is executed.
3630 The stop condition, signaled for example by the built-in target B<stop>, causes
3631 all processing of the value to be stopped immediately.
3635 Causes processing in the current chain to be aborted, but processing of the
3636 value generally will continue. This means that if the chain was called via
3637 B<Jump>, the next target or rule after the jump will be executed. If the chain
3638 was not called by another chain, control will be returned to the daemon and it
3639 may pass the value to another chain.
3643 Most targets will signal the B<continue> condition, meaning that processing
3644 should continue normally. There is no special built-in target for this
3651 The configuration reflects this structure directly:
3653 PostCacheChain "PostCache"
3655 <Rule "ignore_mysql_show">
3658 Type "^mysql_command$"
3659 TypeInstance "^show_"
3669 The above configuration example will ignore all values where the plugin field
3670 is "mysql", the type is "mysql_command" and the type instance begins with
3671 "show_". All other values will be sent to the C<rrdtool> write plugin via the
3672 default target of the chain. Since this chain is run after the value has been
3673 added to the cache, the MySQL C<show_*> command statistics will be available
3674 via the C<unixsock> plugin.
3676 =head2 List of configuration options
3680 =item B<PreCacheChain> I<ChainName>
3682 =item B<PostCacheChain> I<ChainName>
3684 Configure the name of the "pre-cache chain" and the "post-cache chain". The
3685 argument is the name of a I<chain> that should be executed before and/or after
3686 the values have been added to the cache.
3688 To understand the implications, it's important you know what is going on inside
3689 I<collectd>. The following diagram shows how values are passed from the
3690 read-plugins to the write-plugins:
3696 + - - - - V - - - - +
3697 : +---------------+ :
3700 : +-------+-------+ :
3703 : +-------+-------+ : +---------------+
3704 : ! Cache !--->! Value Cache !
3705 : ! insert ! : +---+---+-------+
3706 : +-------+-------+ : ! !
3707 : ! ,------------' !
3709 : +-------+---+---+ : +-------+-------+
3710 : ! Post-Cache +--->! Write-Plugins !
3711 : ! Chain ! : +---------------+
3712 : +---------------+ :
3715 + - - - - - - - - - +
3717 After the values are passed from the "read" plugins to the dispatch functions,
3718 the pre-cache chain is run first. The values are added to the internal cache
3719 afterwards. The post-cache chain is run after the values have been added to the
3720 cache. So why is it such a huge deal if chains are run before or after the
3721 values have been added to this cache?
3723 Targets that change the identifier of a value list should be executed before
3724 the values are added to the cache, so that the name in the cache matches the
3725 name that is used in the "write" plugins. The C<unixsock> plugin, too, uses
3726 this cache to receive a list of all available values. If you change the
3727 identifier after the value list has been added to the cache, this may easily
3728 lead to confusion, but it's not forbidden of course.
3730 The cache is also used to convert counter values to rates. These rates are, for
3731 example, used by the C<value> match (see below). If you use the rate stored in
3732 the cache B<before> the new value is added, you will use the old, B<previous>
3733 rate. Write plugins may use this rate, too, see the C<csv> plugin, for example.
3734 The C<unixsock> plugin uses these rates too, to implement the C<GETVAL>
3737 Last but not last, the B<stop> target makes a difference: If the pre-cache
3738 chain returns the stop condition, the value will not be added to the cache and
3739 the post-cache chain will not be run.
3741 =item B<Chain> I<Name>
3743 Adds a new chain with a certain name. This name can be used to refer to a
3744 specific chain, for example to jump to it.
3746 Within the B<Chain> block, there can be B<Rule> blocks and B<Target> blocks.
3748 =item B<Rule> [I<Name>]
3750 Adds a new rule to the current chain. The name of the rule is optional and
3751 currently has no meaning for the daemon.
3753 Within the B<Rule> block, there may be any number of B<Match> blocks and there
3754 must be at least one B<Target> block.
3756 =item B<Match> I<Name>
3758 Adds a match to a B<Rule> block. The name specifies what kind of match should
3759 be performed. Available matches depend on the plugins that have been loaded.
3761 The arguments inside the B<Match> block are passed to the plugin implementing
3762 the match, so which arguments are valid here depends on the plugin being used.
3763 If you do not need any to pass any arguments to a match, you can use the
3768 Which is equivalent to:
3773 =item B<Target> I<Name>
3775 Add a target to a rule or a default target to a chain. The name specifies what
3776 kind of target is to be added. Which targets are available depends on the
3777 plugins being loaded.
3779 The arguments inside the B<Target> block are passed to the plugin implementing
3780 the target, so which arguments are valid here depends on the plugin being used.
3781 If you do not need any to pass any arguments to a target, you can use the
3786 This is the same as writing:
3793 =head2 Built-in targets
3795 The following targets are built into the core daemon and therefore need no
3796 plugins to be loaded:
3802 Signals the "return" condition, see the L<"Flow control"> section above. This
3803 causes the current chain to stop processing the value and returns control to
3804 the calling chain. The calling chain will continue processing targets and rules
3805 just after the B<jump> target (see below). This is very similar to the
3806 B<RETURN> target of iptables, see L<iptables(8)>.
3808 This target does not have any options.
3816 Signals the "stop" condition, see the L<"Flow control"> section above. This
3817 causes processing of the value to be aborted immediately. This is similar to
3818 the B<DROP> target of iptables, see L<iptables(8)>.
3820 This target does not have any options.
3828 Sends the value to "write" plugins.
3834 =item B<Plugin> I<Name>
3836 Name of the write plugin to which the data should be sent. This option may be
3837 given multiple times to send the data to more than one write plugin.
3841 If no plugin is explicitly specified, the values will be sent to all available
3852 Starts processing the rules of another chain, see L<"Flow control"> above. If
3853 the end of that chain is reached, or a stop condition is encountered,
3854 processing will continue right after the B<jump> target, i.E<nbsp>e. with the
3855 next target or the next rule. This is similar to the B<-j> command line option
3856 of iptables, see L<iptables(8)>.
3862 =item B<Chain> I<Name>
3864 Jumps to the chain I<Name>. This argument is required and may appear only once.
3876 =head2 Available matches
3882 Matches a value using regular expressions.
3888 =item B<Host> I<Regex>
3890 =item B<Plugin> I<Regex>
3892 =item B<PluginInstance> I<Regex>
3894 =item B<Type> I<Regex>
3896 =item B<TypeInstance> I<Regex>
3898 Match values where the given regular expressions match the various fields of
3899 the identifier of a value. If multiple regular expressions are given, B<all>
3900 regexen must match for a value to match.
3907 Host "customer[0-9]+"
3913 Matches values that have a time which differs from the time on the server.
3915 This match is mainly intended for servers that receive values over the
3916 C<network> plugin and write them to disk using the C<rrdtool> plugin. RRDtool
3917 is very sensitive to the timestamp used when updating the RRD files. In
3918 particular, the time must be ever increasing. If a misbehaving client sends one
3919 packet with a timestamp far in the future, all further packets with a correct
3920 time will be ignored because of that one packet. What's worse, such corrupted
3921 RRD files are hard to fix.
3923 This match lets one match all values B<outside> a specified time range
3924 (relative to the server's time), so you can use the B<stop> target (see below)
3925 to ignore the value, for example.
3931 =item B<Future> I<Seconds>
3933 Matches all values that are I<ahead> of the server's time by I<Seconds> or more
3934 seconds. Set to zero for no limit. Either B<Future> or B<Past> must be
3937 =item B<Past> I<Seconds>
3939 Matches all values that are I<behind> of the server's time by I<Seconds> or
3940 more seconds. Set to zero for no limit. Either B<Future> or B<Past> must be
3952 This example matches all values that are five minutes or more ahead of the
3953 server or one hour (or more) lagging behind.
3957 Matches the actual value of data sources against given minimumE<nbsp>/ maximum
3958 values. If a data-set consists of more than one data-source, all data-sources
3959 must match the specified ranges for a positive match.
3965 =item B<Min> I<Value>
3967 Sets the smallest value which still results in a match. If unset, behaves like
3970 =item B<Max> I<Value>
3972 Sets the largest value which still results in a match. If unset, behaves like
3975 =item B<Invert> B<true>|B<false>
3977 Inverts the selection. If the B<Min> and B<Max> settings result in a match,
3978 no-match is returned and vice versa. Please note that the B<Invert> setting
3979 only effects how B<Min> and B<Max> are applied to a specific value. Especially
3980 the B<DataSource> and B<Satisfy> settings (see below) are not inverted.
3982 =item B<DataSource> I<DSName> [I<DSName> ...]
3984 Select one or more of the data sources. If no data source is configured, all
3985 data sources will be checked. If the type handled by the match does not have a
3986 data source of the specified name(s), this will always result in no match
3987 (independent of the B<Invert> setting).
3989 =item B<Satisfy> B<Any>|B<All>
3991 Specifies how checking with several data sources is performed. If set to
3992 B<Any>, the match succeeds if one of the data sources is in the configured
3993 range. If set to B<All> the match only succeeds if all data sources are within
3994 the configured range. Default is B<All>.
3996 Usually B<All> is used for positive matches, B<Any> is used for negative
3997 matches. This means that with B<All> you usually check that all values are in a
3998 "good" range, while with B<Any> you check if any value is within a "bad" range
3999 (or outside the "good" range).
4003 Either B<Min> or B<Max>, but not both, may be unset.
4007 # Match all values smaller than or equal to 100. Matches only if all data
4008 # sources are below 100.
4014 # Match if the value of any data source is outside the range of 0 - 100.
4024 =head2 Available targets
4028 =item B<notification>
4030 Creates and dispatches a notification.
4036 =item B<Message> I<String>
4038 This required option sets the message of the notification. The following
4039 placeholders will be replaced by an appropriate value:
4047 =item B<%{plugin_instance}>
4051 =item B<%{type_instance}>
4053 These placeholders are replaced by the identifier field of the same name.
4055 =item B<%{ds:>I<name>B<}>
4057 These placeholders are replaced by a (hopefully) human readable representation
4058 of the current rate of this data source. If you changed the instance name
4059 (using the B<set> or B<replace> targets, see below), it may not be possible to
4060 convert counter values to rates.
4064 Please note that these placeholders are B<case sensitive>!
4066 =item B<Severity> B<"FATAL">|B<"WARNING">|B<"OKAY">
4068 Sets the severity of the message. If omitted, the severity B<"WARNING"> is
4075 <Target "notification">
4076 Message "Oops, the %{type_instance} temperature is currently %{ds:value}!"
4082 Replaces parts of the identifier using regular expressions.
4088 =item B<Host> I<Regex> I<Replacement>
4090 =item B<Plugin> I<Regex> I<Replacement>
4092 =item B<PluginInstance> I<Regex> I<Replacement>
4094 =item B<TypeInstance> I<Regex> I<Replacement>
4096 Match the appropriate field with the given regular expression I<Regex>. If the
4097 regular expression matches, that part that matches is replaced with
4098 I<Replacement>. If multiple places of the input buffer match a given regular
4099 expression, only the first occurrence will be replaced.
4101 You can specify each option multiple times to use multiple regular expressions
4109 # Replace "example.net" with "example.com"
4110 Host "\\<example.net\\>" "example.com"
4112 # Strip "www." from hostnames
4118 Sets part of the identifier of a value to a given string.
4124 =item B<Host> I<String>
4126 =item B<Plugin> I<String>
4128 =item B<PluginInstance> I<String>
4130 =item B<TypeInstance> I<String>
4132 Set the appropriate field to the given string. The strings for plugin instance
4133 and type instance may be empty, the strings for host and plugin may not be
4134 empty. It's currently not possible to set the type of a value this way.
4141 PluginInstance "coretemp"
4142 TypeInstance "core3"
4147 =head2 Backwards compatibility
4149 If you use collectd with an old configuration, i.E<nbsp>e. one without a
4150 B<Chain> block, it will behave as it used to. This is equivalent to the
4151 following configuration:
4157 If you specify a B<PostCacheChain>, the B<write> target will not be added
4158 anywhere and you will have to make sure that it is called where appropriate. We
4159 suggest to add the above snippet as default target to your "PostCache" chain.
4163 Ignore all values, where the hostname does not contain a dot, i.E<nbsp>e. can't
4179 L<collectd-exec(5)>,
4180 L<collectd-perl(5)>,
4181 L<collectd-unixsock(5)>,
4194 Florian Forster E<lt>octo@verplant.orgE<gt>