Your company here — click to reach over 10,000 unique daily visitors

collectdctl - Man Page

Control interface for collectd


collectdctl [options] <command> [command options]


collectdctl provides a control interface for collectd, which may be used to interact with the daemon using the unixsock plugin.


collectdctl supports the following options:

-s socket

Path to the UNIX socket opened by collectd's unixsock plugin. Default: /var/run/collectd-unixsock


Display usage information and exit.

Available Commands

The following commands are supported:

getval <identifier>

Query the latest collected value identified by the specified <identifier> (see below). The value-list associated with that data-set is returned as a list of key-value-pairs, each on its own line. Keys and values are separated by the equal sign (=).

flush [timeout=<seconds>] [plugin=<name>] [identifier=<id>]

Flush the daemon. This is useful, e. g., to make sure that the latest values have been written to the respective RRD file before graphing them or copying them to somewhere else.

The following options are supported by the flush command:


Flush values older than the specified timeout (in seconds) only.


Flush the specified plugin only. I. e., data cached by the specified plugin is written to disk (or network or whatever), if the plugin supports that operation.

Example: rrdtool.


If this option is present, only the data specified by the specified identifier (see below) will be flushed. Note that this option is not supported by all plugins (e. g., the network plugin does not support this).

The plugin and identifier options may be specified more than once. In that case, all combinations of specified plugins and identifiers will be flushed only.


Returns a list of all values (by their identifier) available to the unixsock plugin. Each value is printed on its own line. I. e., this command returns a list of valid identifiers that may be used with the other commands.

putval <identifier> [interval=<seconds>] <value-list(s)>

Submit one or more values (identified by <identifier>, see below) to the daemon which will then dispatch them to the write plugins. interval specifies the interval (in seconds) used to collect the values following that option. It defaults to the default of the running collectd instance receiving the data. Multiple <value-list(s)> (see below) may be specified. Each of them will be submitted to the daemon. The values have to match the data-set definition specified by the type as given in the identifier (see types.db(5) for details).


An identifier has the following format:



Hostname defaults to the local (non-fully qualified) hostname if omitted. No error is returned if the specified identifier does not exist (this is a limitation in the libcollectdclient library).


A value list describes one data-set as handled by collectd. It is a colon (:) separated list of the time and the values. Each value is either given as an integer if the data-type is a counter, or as a double if the data-type is a gauge value. A literal U is interpreted as an undefined gauge value. The number of values and the data-types have to match the type specified in the identifier (see types.db(5) for details). The time is specified as epoch (i. e., standard UNIX time) or as a literal N which will be interpreted as now.


collectdctl flush plugin=rrdtool identifier=somehost/cpu-0/cpu-wait

Flushes all CPU wait RRD values of the first CPU of the local host. I. e., writes all pending RRD updates of that data-source to disk.

for ident in `collectdctl listval | grep users/users`; do collectdctl getval $ident; done

Query the latest number of logged in users on all hosts known to the local collectd instance.

See Also

collectd(1), collectd.conf(5), collectd-unixsock(5), types.db(5)


collectd has been written by Florian Forster <octo at collectd.org> and many contributors (see `AUTHORS').

collectdctl has been written by HXkon J Dugstad Johnsen <hakon-dugstad.johnsen at telenor.com> and Sebastian Harl <sh at tokkee.org>.


2020-07-20 collectd