X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=src%2Fcollectd.conf.pod;h=aaeeaf419b703913392ef5e78448ffa76fc451dc;hb=3348ace2cdd95bc1de5e28d11f3999cf5bd4ebf4;hp=b2aab2139e1ce45633e2004609955c7e5b5a13f6;hpb=10a3718bdf7761e247b06808b8c72ca75cb0e0ba;p=collectd.git

diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index b2aab213..aaeeaf41 100644
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -510,10 +510,12 @@ are disabled by default.
 
 =head2 Plugin C<amqp>
 
-The I<AMQMP plugin> can be used to communicate with other instances of
+The I<AMQP plugin> can be used to communicate with other instances of
 I<collectd> or third party applications using an AMQP message broker. Values
 are sent to or received from the broker, which handles routing, queueing and
-possibly filtering or messages.
+possibly filtering out messages.
+
+B<Synopsis:>
 
  <Plugin "amqp">
    # Send values to an AMQP broker
@@ -2286,7 +2288,7 @@ expected from them. This is documented in great detail in L<collectd-exec(5)>.
 =head2 Plugin C<fhcount>
 
 The C<fhcount> plugin provides statistics about used, unused and total number of
-file handles.
+file handles on Linux.
 
 The I<fhcount plugin> provides the following configuration options:
 
@@ -3233,6 +3235,114 @@ B<Collect> option is mandatory.
 
 =back
 
+=head2 Plugin C<mqtt>
+
+The I<MQTT plugin> can send metrics to MQTT (B<Publish> blocks) and receive
+values from MQTT (B<Subscribe> blocks).
+
+B<Synopsis:>
+
+ <Plugin mqtt>
+   <Publish "name">
+     Host "mqtt.example.com"
+     Prefix "collectd"
+   </Publish>
+   <Subscribe "name">
+     Host "mqtt.example.com"
+     Topic "collectd/#"
+   </Subscribe>
+ </Plugin>
+
+The plugin's configuration is in B<Publish> and/or B<Subscribe> blocks,
+configuring the sending and receiving direction respectively. The plugin will
+register a write callback named C<mqtt/I<name>> where I<name> is the string
+argument given to the B<Publish> block. Both types of blocks share many but not
+all of the following options. If an option is valid in only one of the blocks,
+it will be mentioned explicitly.
+
+B<Options:>
+
+=over 4
+
+=item B<Host> I<Hostname>
+
+Hostname of the MQTT broker to connect to.
+
+=item B<Port> I<Service>
+
+Port number or service name of the MQTT broker to connect to.
+
+=item B<User> I<UserName>
+
+Username used when authenticating to the MQTT broker.
+
+=item B<Password> I<Password>
+
+Password used when authenticating to the MQTT broker.
+
+=item B<ClientId> I<ClientId>
+
+MQTT client ID to use. Defaults to the hostname used by I<collectd>.
+
+=item B<QoS> [B<0>-B<2>]
+
+Sets the I<Quality of Service>, with the values C<0>, C<1> and C<2> meaning:
+
+=over 4
+
+=item B<0>
+
+At most once
+
+=item B<1>
+
+At least once
+
+=item B<2>
+
+Exactly once
+
+=back
+
+In B<Publish> blocks, this option determines the QoS flag set on outgoing
+messages and defaults to B<0>. In B<Subscribe> blocks, determines the maximum
+QoS setting the client is going to accept and defaults to B<2>. If the QoS flag
+on a message is larger than the maximum accepted QoS of a subscriber, the
+message's QoS will be downgraded.
+
+=item B<Prefix> I<Prefix> (Publish only)
+
+This plugin will use one topic per I<value list> which will looks like a path.
+I<Prefix> is used as the first path element and defaults to B<collectd>.
+
+An example topic name would be:
+
+ collectd/cpu-0/cpu-user
+
+=item B<Retain> B<false>|B<true> (Publish only)
+
+Controls whether the MQTT broker will retain (keep a copy of) the last message
+sent to each topic and deliver it to new subscribers. Defaults to B<false>.
+
+=item B<StoreRates> B<true>|B<false> (Publish only)
+
+Controls whether C<DERIVE> and C<COUNTER> metrics are converted to a I<rate>
+before sending. Defaults to B<true>.
+
+=item B<CleanSession> B<true>|B<false> (Subscribe only)
+
+Controls whether the MQTT "cleans" the session up after the subscriber
+disconnects or if it maintains the subscriber's subscriptions and all messages
+that arrive while the subscriber is disconnected. Defaults to B<true>.
+
+=item B<Topic> I<TopicName> (Subscribe only)
+
+Configures the topic(s) to subscribe to. You can use the single level C<+> and
+multi level C<#> wildcards. Defaults to B<collectd/#>, i.e. all topics beneath
+the B<collectd> branch.
+
+=back
+
 =head2 Plugin C<mysql>
 
 The C<mysql plugin> requires B<mysqlclient> to be installed. It connects to
@@ -7009,6 +7119,10 @@ You can also specify combinations of these fields. For example B<name uuid>
 means to concatenate the guest name and UUID (with a literal colon character
 between, thus I<"foo:1234-1234-1234-1234">).
 
+At the moment of writing (collectd-5.5), hostname string is limited to 62
+characters. In case when combination of fields exceeds 62 characters,
+hostname will be truncated without a warning.
+
 =item B<InterfaceFormat> B<name>|B<address>
 
 When the virt plugin logs interface data, it sets the name of the collected
@@ -7495,15 +7609,17 @@ Synopsis:
         Port "6379"
         Timeout 1000
         Prefix "collectd/"
+        Database 1
     </Node>
   </Plugin>
 
 Values are submitted to I<Sorted Sets>, using the metric name as the key, and
 the timestamp as the score. Retrieving a date range can then be done using the
-C<ZRANGEBYSCORE> I<Redis> command. Additionnally, all the identifiers of these
+C<ZRANGEBYSCORE> I<Redis> command. Additionally, all the identifiers of these
 I<Sorted Sets> are kept in a I<Set> called C<collectd/values> (or
 C<${prefix}/values> if the B<Prefix> option was specified) and can be retrieved
-using the C<SMEMBERS> I<Redis> command. See
+using the C<SMEMBERS> I<Redis> command. You can specify the database to use 
+with the B<Database> parameter (default is C<0>). See
 L<http://redis.io/commands#sorted_set> and L<http://redis.io/commands#set> for
 details.
 
@@ -7519,9 +7635,9 @@ options are available:
 =item B<Node> I<Nodename>
 
 The B<Node> block identifies a new I<Redis> node, that is a new I<Redis>
-instance running in an specified host and port. The name for node is a
+instance running on a specified host and port. The node name is a
 canonical identifier which is used as I<plugin instance>. It is limited to
-64E<nbsp>characters in length.
+51E<nbsp>characters in length.
 
 =item B<Host> I<Hostname>
 
@@ -7545,6 +7661,10 @@ containing all metrics. Defaults to C<collectd/>, so metrics will have names
 like C<collectd/cpu-0/cpu-user>. When setting this to something different, it
 is recommended but not required to include a trailing slash in I<Prefix>.
 
+=item B<Database> I<Index>
+
+This index selects the redis database to use for writing operations. Defaults to C<0>.
+
 =back
 
 =head2 Plugin C<write_riemann>