bionic (5) collectd-unixsock.5.gz

Provided by: collectd-core_5.7.2-2ubuntu1.2_amd64 bug

NAME

       collectd-unixsock - Documentation of collectd's "unixsock plugin"

SYNOPSIS

         # See collectd.conf(5)
         LoadPlugin unixsock
         # ...
         <Plugin unixsock>
           SocketFile "/path/to/socket"
           SocketGroup "collectd"
           SocketPerms "0770"
           DeleteSocket false
         </Plugin>

DESCRIPTION

       The "unixsock plugin" opens an UNIX-socket over which one can interact with the daemon. This can be used
       to use the values collected by collectd in other applications, such as monitoring solutions, or submit
       externally collected values to collectd.

       For example, this plugin is used by collectd-nagios(1) to check if some value is in a certain range and
       exit with a Nagios-compatible exit code.

COMMANDS

       Upon start the "unixsock plugin" opens a UNIX-socket and waits for connections. Once a connection is
       established the client can send commands to the daemon which it will answer, if it understand them.

       In general the plugin answers with a status line of the following form:

       Status Message

       If Status is greater than or equal to zero the message indicates success, if Status is less than zero the
       message indicates failure. Message is a human-readable string that further describes the return value.

       On success, Status furthermore indicates the number of subsequent lines of output (not including the
       status line). Each such lines usually contains a single return value. See the description of each command
       for details.

       The following commands are implemented:

       GETVAL Identifier
           If the value identified by Identifier (see below) is found the complete value-list is returned. The
           response is a list of name-value-pairs, each pair on its own line (the number of lines is indicated
           by the status line - see above). Each name-value-pair is of the form name=value.  Counter-values are
           converted to a rate, e. g. bytes per second.  Undefined values are returned as NaN.

           Example:
             -> | GETVAL myhost/cpu-0/cpu-user
             <- | 1 Value found
             <- | value=1.260000e+00

       LISTVAL
           Returns a list of the values available in the value cache together with the time of the last update,
           so that querying applications can issue a GETVAL command for the values that have changed. Each
           return value consists of the update time as an epoch value and the identifier, separated by a space.
           The update time is the time of the last value, as provided by the collecting instance and may be very
           different from the time the server considers to be "now".

           Example:
             -> | LISTVAL
             <- | 69 Values found
             <- | 1182204284 myhost/cpu-0/cpu-idle
             <- | 1182204284 myhost/cpu-0/cpu-nice
             <- | 1182204284 myhost/cpu-0/cpu-system
             <- | 1182204284 myhost/cpu-0/cpu-user
             ...

       PUTVAL Identifier [OptionList] Valuelist
           Submits one or more values (identified by Identifier, see below) to the daemon which will dispatch it
           to all it's write-plugins.

           An Identifier is of the form "host/plugin-instance/type-instance" with both instance-parts being
           optional. If they're omitted the hyphen must be omitted, too. plugin and each instance-part may be
           chosen freely as long as the tuple (plugin, plugin instance, type instance) uniquely identifies the
           plugin within collectd. type identifies the type and number of values (i. e. data-set) passed to
           collectd. A large list of predefined data-sets is available in the types.db file.

           The OptionList is an optional list of Options, where each option is a key-value-pair. A list of
           currently understood options can be found below, all other options will be ignored. Values that
           contain spaces must be quoted with double quotes.

           Valuelist is a colon-separated list of the time and the values, each either an integer if the data-
           source is a counter, or a double if the data-source is of type "gauge". You can submit an undefined
           gauge-value by using U. When submitting U to a counter the behavior is undefined. The time is given
           as epoch (i. e. standard UNIX time).

           You can mix options and values, but the order is important: Options only effect following values, so
           specifying an option as last field is allowed, but useless. Also, an option applies to all following
           values, so you don't need to re-set an option over and over again.

           The currently defined Options are:

           interval=seconds
               Gives the interval in which the data identified by Identifier is being collected.

           Please note that this is the same format as used in the exec plugin, see collectd-exec(5).

           Example:
             -> | PUTVAL testhost/interface/if_octets-test0 interval=10 1179574444:123:456
             <- | 0 Success

       PUTNOTIF [OptionList] message=Message
           Submits a notification to the daemon which will then dispatch it to all plugins which have registered
           for receiving notifications.

           The PUTNOTIF command is followed by a list of options which further describe the notification. The
           message option is special in that it will consume the rest of the line as its value. The message,
           severity, and time options are mandatory.

           Valid options are:

           message=Message (REQUIRED)
               Sets the message of the notification. This is the message that will be made accessible to the
               user, so it should contain some useful information. As with all options: If the message includes
               spaces, it must be quoted with double quotes. This option is mandatory.

           severity=failure|warning|okay (REQUIRED)
               Sets the severity of the notification. This option is mandatory.

           time=Time (REQUIRED)
               Sets the time of the notification. The time is given as "epoch", i. e. as seconds since January
               1st, 1970, 00:00:00. This option is mandatory.

           host=Hostname
           plugin=Plugin
           plugin_instance=Plugin-Instance
           type=Type
           type_instance=Type-Instance
               These "associative" options establish a relation between this notification and collected
               performance data. This connection is purely informal, i. e. the daemon itself doesn't do anything
               with this information. However, websites or GUIs may use this information to place notifications
               near the affected graph or table. All the options are optional, but plugin_instance without
               plugin or type_instance without type doesn't make much sense and should be avoided.

           type:key=value
               Sets user defined meta information. The type key is a single character defining the type of the
               meta information.

               The current supported types are:

               s A string passed as-is.

           Please note that this is the same format as used in the exec plugin, see collectd-exec(5).

           Example:
             -> | PUTNOTIF type=temperature severity=warning time=1201094702 message=The roof is on fire!
             <- | 0 Success

       FLUSH [timeout=Timeout] [plugin=Plugin [...]] [identifier=Ident [...]]
           Flushes all cached data older than Timeout seconds. If no timeout has been specified, it defaults to
           -1 which causes all data to be flushed.

           If the plugin option has been specified, only the Plugin plugin will be flushed. You can have
           multiple plugin options to flush multiple plugins in one go. If the plugin option is not given all
           plugins providing a flush callback will be flushed.

           If the identifier option is given only the specified values will be flushed.  This is meant to be
           used by graphing or displaying frontends which want to have the latest values for a specific graph.
           Again, you can specify the identifier option multiple times to flush several values. If this option
           is not specified at all, all values will be flushed.

           Example:
             -> | FLUSH plugin=rrdtool identifier=localhost/df/df-root identifier=localhost/df/df-var
             <- | 0 Done: 2 successful, 0 errors

   Identifiers
       Value or value-lists are identified in a uniform fashion:

       Hostname/Plugin/Type

       Where Plugin and Type are both either of type "Name" or "Name-Instance". If the identifier includes
       spaces, it must be quoted using double quotes. This sounds more complicated than it is, so here are some
       examples:

         myhost/cpu-0/cpu-user
         myhost/load/load
         myhost/memory/memory-used
         myhost/disk-sda/disk_octets
         "myups/snmp/temperature-Outlet 1"

ABSTRACTION LAYER

       collectd ships the Perl-Module Collectd::Unixsock which provides an abstraction layer over the actual
       socket connection. It can be found in the directory bindings/perl/ in the source distribution or
       (usually) somewhere near /usr/share/perl5/ if you're using a package. If you want to use Perl to
       communicate with the daemon, you're encouraged to use and expand this module.

SEE ALSO

       collectd(1), collectd.conf(5), collectd-nagios(1), unix(7)

AUTHOR

       Florian Forster <octo@collectd.org>