1 collectd - System information collection daemon
2 =================================================
8 collectd is a small daemon which collects statistics about a computer's
9 usage and writes then into RRD files.
15 * collectd is able to collect the following data:
18 Apache server utilization: Number of bytes transfered, number of
19 requests handled and detailed scoreboard statistics
22 APC UPS Daemon: UPS charge, load, input/output/battery voltage, etc.
25 Sensors in Macs running Mac OS X / Darwin: Temperature, fanspeed and
29 Batterycharge, -current and voltage of ACPI and PMU based laptop
33 CPU utilization: Time spent in the system, user, nice, idle, and related
37 CPU frequency (For laptops with speed step or a similar technology)
40 Mountpoint usage (Basically the values `df(1)' delivers)
43 Disk utilization: Sectors read/written, number of read/write actions,
44 average time an IO-operation took to complete.
47 DNS traffic: Query types, response codes, opcodes and traffic/octets
51 Email statistics: Count, traffic, spam scores and checks.
52 See collectd-email(5).
55 Amount of entropy available to the system.
58 Values gathered by a custom program or script.
62 Harddisk temperatures using hddtempd.
65 Interface traffic: Number of octets, packets and errors for each
69 Iptables' counters: Number of bytes that were matched by a certain
73 IPVS connection statistics (number of connections, octets and packets
74 for each service and destination).
75 See http://www.linuxvirtualserver.org/software/index.html.
78 IRQ counters: Frequency in which certain interrupts occur.
81 System load average over the last 1, 5 and 15 minutes.
84 Motherboard sensors: temperature, fanspeed and voltage information,
88 Memory utilization: Memory occupied by running processes, page cache,
89 buffer cache and free.
92 Information provided by serial multimeters, such as the `Metex
96 MySQL server statistics: Commands issued, handlers triggered, thread
97 usage, query cache utilization and traffic/octets sent and received.
100 Very detailed Linux network interface and routing statistics. You can get
101 (detailed) information on interfaces, qdiscs, classes, and, if you can
102 make use of it, filters.
105 Receive values that were collected by other hosts. Large setups will
106 want to collect the data on one dedicated machine, and this is the
107 plugin of choice for that.
110 NFS Procedures: Which NFS command were called how often. Only NFSv2 and
114 NTP daemon statistics: Local clock drift, offset to peers, etc.
117 Network UPS tools: UPS current, voltage, power, charge, utilisation,
118 temperature, etc. See upsd(8).
121 The perl plugin implements a Perl-interpreter into collectd. You can
122 write your own plugins in Perl and return arbitrary values using this
123 API. See collectd-perl(5).
125 This plugin is still considered to be experimental and subject to change
126 between minor releases.
129 Network latency: Time to reach the default gateway or another given
133 Process counts: Number of running, sleeping, zombie, ... processes.
136 System sensors, accessed using lm_sensors: Voltages, temperatures and
140 RX and TX of serial interfaces. Linux only; needs root privileges.
143 Read values from SNMP (Simple Network Management Protocol) enabled
144 network devices such as switches, routers, thermometers, rack monitoring
145 servers, etc. See collectd-snmp(5).
148 Pages swapped out onto harddisk or whatever is called `swap' by the OS..
151 Bytes and operations read and written on tape devices. Solaris only.
154 Number of TCP connections to specific local and remote ports.
157 Users currently logged in.
160 System resources used by Linux VServers.
161 See <http://linux-vserver.org/>.
164 Link quality of wireless cards. Linux only.
167 Bitrate and frequency of music played with XMMS.
169 * Output can be written or send to various destinations by the following
173 Write to comma separated values (CSV) files. This needs lots of
174 diskspace but is extremely portable and can be analysed with almost
175 every program that can analyse anything. Even Microsoft's Excel..
178 Send the data to a remote host to save the data somehow. This is useful
179 for large setups where the data should be saved by a dedicated machine.
182 Of course the values are propagated to plugins written in Perl, too, so
183 you can easily do weird stuff with the plugins we didn't dare think of
184 ;) See collectd-perl(5).
187 Output to round-robin-database (RRD) files using librrd. See rrdtool(1).
188 This is likely the most popular destination for such values. Since
189 updates to RRD-files are somewhat expensive this plugin can cache
190 updates to the files and write a bunch of updates at once, which lessens
194 One can query the values from the unixsock plugin whenever they're
195 needed. Please read collectd-unixsock(5) for a description on how that's
198 * Logging is, as everything in collectd, provided by plugins. The following
199 plugins keep up informed about what's going on:
202 Writes logmessages to a file or STDOUT/STDERR.
205 Logs to the standard UNIX logging mechanism, syslog.
207 * Performance: Since collectd is running as a daemon it doesn't spend much
208 time starting up again and again. With the exception of the exec plugin no
209 processes are forked. Caching in output plugins, such as the rrdtool and
210 network plugins, makes sure your resources are used efficiently. Also,
211 since collectd is programmed multithreaded it benefits from hyperthreading
212 and multicore processors and makes sure that the daemon isn't idle if only
213 one plugins waits for an IO-operation to complete.
215 * Once set up, hardly any maintenance is necessary. Setup is kept as easy
216 as possible and the default values should be okay for most users.
222 * collectd's configuration file can be found at `sysconfdir'/collectd.conf.
223 Run `collectd -h' for a list of builtin defaults. See `collectd.conf(5)'
224 for a list of options and a syntax description.
226 * When the `csv' or `rrdtool' plugins are loaded they'll write the values to
227 files. The usual place for these files is beneath `/var/lib/collectd'.
229 * When using some of the plugins, collectd needs to run as user root, since
230 only root can do certain things, such as craft ICMP packages needed to ping
231 other hosts. collectd should NOT be installed setuid root since it can be
232 used to overwrite valuable files!
234 * Sample scripts to generate graphs reside in `contrib/' in the source
235 package or somewhere near `/usr/share/doc/collectd' in most distributions.
236 Please be aware that those script are meant as a starting point for your
237 own experiments.. Some of them require the `RRDs' Perl module.
238 (`librrds-perl' on Debian) If you have written a more sophisticated
239 solution please share it with us.
241 * The RRAs of the automatically created RRD files depend on the `step'
242 and `heartbeat' settings given. If change these settings you may need to
243 re-create the files, losing all data. Please be aware of that when changing
244 the values and read the rrdtool(1) manpage thoroughly.
247 collectd and chkrootkit
248 -----------------------
250 If you are using the `dns' plugin chkrootkit(1) will report collectd as a
251 packet sniffer ("<iface>: PACKET SNIFFER(/usr/sbin/collectd[<pid>])"). The
252 plugin captures all UDP packets on port 53 to analyze the DNS traffic. In
253 this case, collectd is a legitimate sniffer and the report should be
254 considered to be a false positive. However, you might want to check that
255 this really is collectd and not some other, illegitimate sniffer.
261 To compile collectd from source you will need:
263 * Usual suspects: C compiler, linker, preprocessor, make, ...
265 * A POSIX-threads (pthread) implementation.
266 Since gathering some statistics is slow (network connections, slow devices,
267 etc) the collectd is parallelized. The POSIX threads interface is being
268 used and should be found in various implementations for hopefully all
272 If you want to use the `apache' plugin
275 For querying iptables counters.
277 * libmysqlclient (optional)
279 * libnetlink (optional)
281 * libnetsnmp (optional)
283 * liboping (optional, if not found a version shipped with this distribution
285 Used by the `ping' plugin to send and receive ICMP packets.
288 Used to capture packets by the `dns' plugin.
290 * librrd (optional; headers and library; rrdtool 1.0 and 1.2 both work fine)
291 If built without `librrd' the resulting binary will be `client only', i.e.
292 will send its values via multicast and not create any RRD files itself.
293 Alternatively you can chose to write CSV-files (Comma Separated Values)
296 * libsensors (optional)
297 To read from `lm_sensors'.
299 * libstatgrab may be used to collect statistics on systems other than Linux
300 and/or Solaris. Note that CPU- and disk-statistics, while being provided
301 by this library, are not supported in collectd right now..
302 <http://www.i-scream.org/libstatgrab/>
304 * libupsclient/nut (optional)
305 For the `nut' plugin which queries nut's `upsd'.
309 * librt, libsocket, libkstat, libdevinfo
310 Various standard Solaris libraries which provide system functions.
312 * CoreFoundation.framework and IOKit.framework
313 For compiling on Darwin in general and the `apple_sensors' plugin in
320 To compile correctly collectd needs to be able to initialize static
321 variables to NAN (Not A Number). Some C libraries, especially the GNU
322 libc, have a problem with that.
324 Luckily, with GCC it's possible to work around that problem: One can define
325 NAN as being (0.0 / 0.0) and `isnan' as `f != f'. However, to test this
326 ``implementation'' the configure script needs to compile and run a short
327 test program. Obviously running a test program when doing a cross-
328 compilation is, well, challenging.
330 If you run into this problem, you can use the `--with-nan-emulation'
331 configure option to force the use of this implementation. We can't promise
332 that the compiled binary actually behaves as it should, but since NANs
333 are likely never passed to the libm you have a good chance to be lucky.
339 For questions, bugreports, development information and basically all other
340 concerns please send an email to collectd's mailinglist at
341 <collectd at verplant.org>.
343 For live discussion and more personal contact visit us in IRC, we're in
344 channel #collectd on freenode.
350 Florian octo Forster <octo at verplant.org>,
351 Sebastian tokkee Harl <sh at tokkee.org>,
352 and many contributors (see `AUTHORS').
354 Please send bugreports and patches to the mailinglist, see `Contact' above.