=back
+=head2 Plugin C<bind>
+
+Starting with BIND 9.5.0, the most widely used DNS server software provides
+extensive statistics about queries, responses and lots of other information.
+The bind plugin retrieves this information that's encoded in XML and provided
+via HTTP and submits the values to collectd.
+
+To use this plugin, you first need to tell BIND to make this information
+available. This is done with the C<statistics-channels> configuration option:
+
+ statistics-channels {
+ inet localhost port 8053;
+ };
+
+The bind plugin accepts the following configuration options:
+
+=over 4
+
+=item B<URL> I<URL>
+
+URL from which to retrieve the XML data. If not specified,
+C<http://localhost:8053/> will be used.
+
+=item B<DNSSEC> I<true>|I<false>
+
+=item B<OpCodes> I<true>|I<false>
+
+=item B<Queries> I<true>|I<false>
+
+=item B<QueryResults> I<true>|I<false>
+
+=item B<RCode> I<true>|I<false>
+
+=item B<Rejects> I<true>|I<false>
+
+=item B<Requests> I<true>|I<false>
+
+=item B<Resolver> I<true>|I<false>
+
+=item B<Responses> I<true>|I<false>
+
+=item B<RRQueriesIn> I<true>|I<false>
+
+=item B<Updates> I<true>|I<false>
+
+=item B<ZoneMaintenance> I<true>|I<false>
+
+=item B<ZoneStats> I<true>|I<false>
+
+Enables or disables collection of specific counters.
+TODO: Options must be described in detail!
+
+=back
+
=head2 Plugin C<cpufreq>
This plugin doesn't have any options. It reads
Set the directory to store CSV-files under. Per default CSV-files are generated
beneath the daemon's working directory, i.E<nbsp>e. the B<BaseDir>.
+The special strings B<stdout> and B<stderr> can be used to write to the standard
+output and standard error channels, respectively. This, of course, only makes
+much sense when collectd is running in foreground- or non-daemon-mode.
=item B<StoreRates> B<true|false>
=back
+=head2 Plugin C<dbi>
+
+This plugin uses the B<dbi> library (L<http://libdbi.sourceforge.net/>) to
+connect to various databases, execute I<SQL> statements and read back the
+results. I<dbi> is an acronym for "database interface" in case you were
+wondering about the name. You can configure how each column is to be
+interpreted and the plugin will generate one or more data sets from each row
+returned according to these rules.
+
+Because the plugin is very generic, the configuration is a little more complex
+than those of other plugins. It usually looks something like this:
+
+ <Plugin dbi>
+ <Query "out_of_stock">
+ Statement "SELECT category, COUNT(*) AS value FROM products WHERE in_stock = 0 GROUP BY category"
+ <Result>
+ Type "gauge"
+ InstancesFrom "category"
+ ValuesFrom "value"
+ </Result>
+ </Query>
+ <Database "product_information">
+ Driver "mysql"
+ DriverOption "host" "localhost"
+ DriverOption "username" "collectd"
+ DriverOption "password" "aZo6daiw"
+ DriverOption "dbname" "prod_info"
+ SelectDB "prod_info"
+ Query "out_of_stock"
+ </Database>
+ </Plugin>
+
+The configuration above defines one query with one result and one database. The
+query is then linked to the database with the B<Query> option I<within> the
+B<E<lt>DatabaseE<gt>> block. You can have any number of queries and databases
+and you can also use the B<Include> statement to split up the configuration
+file in multiple, smaller files. However, the B<E<lt>QueryE<gt>> block I<must>
+precede the B<E<lt>DatabaseE<gt>> blocks, because the file is interpreted from
+top to bottom!
+
+The following is a complete list of options:
+
+=head3 B<Query> blocks
+
+Query blocks define I<SQL> statements and how the returned data should be
+interpreted. They are identified by the name that is given in the opening line
+of the block. Thus the name needs to be unique. Other than that, the name is
+not used in collectd.
+
+In each B<Query> block, there is one or more B<Result> blocks. B<Result> blocks
+define which column holds which value or instance information. You can use
+multiple B<Result> blocks to create multiple values from one returned row. This
+is especially useful, when queries take a long time and sending almost the same
+query again and again is not desirable.
+
+Example:
+
+ <Query "environment">
+ Statement "select station, temperature, humidity from environment"
+ <Result>
+ Type "temperature"
+ InstancesFrom "station"
+ ValuesFrom "temperature"
+ </Result>
+ <Result>
+ Type "humidity"
+ InstancesFrom "station"
+ ValuesFrom "humidity"
+ </Result>
+ </Query>
+
+The following options are accepted:
+
+=over 4
+
+=item B<Statement> I<SQL>
+
+Sets the statement that should be executed on the server. This is B<not>
+interpreted by collectd, but simply passed to the database server. Therefore,
+the SQL dialect that's used depends on the server collectd is connected to.
+
+The query has to return at least two columns, one for the instance and one
+value. You cannot omit the instance, even if the statement is guaranteed to
+always return exactly one line. In that case, you can usually specify something
+like this:
+
+ Statement "SELECT \"instance\", COUNT(*) AS value FROM table"
+
+(That works with MySQL but may not be valid SQL according to the spec. If you
+use a more strict database server, you may have to select from a dummy table or
+something.)
+
+=item B<Type> I<Type>
+
+The B<type> that's used for each line returned. See L<types.db(5)> for more
+details on how types are defined. In short: A type is a predefined layout of
+data and the number of values and type of values has to match the type
+definition.
+
+If you specify "temperature" here, you need exactly one gauge column. If you
+specify "if_octets", you will need two counter columns. See the B<ValuesFrom>
+setting below.
+
+There must be exactly one B<Type> option inside each B<Result> block.
+
+=item B<InstancesFrom> I<column0> [I<column1> ...]
+
+Specifies the columns whose values will be used to create the "TypeInstance"
+for each row. You need to specify at least one column for each query. If you
+specify more than one column, the value of all columns will be join together
+with the hyphen as separation character.
+
+The plugin itself does not check whether or not all built instances are
+different. It's your responsibility to assure that each is unique.
+
+There must be at least one B<InstancesFrom> option inside each B<Result> block.
+
+=item B<ValuesFrom> I<column0> [I<column1> ...]
+
+Names the columns whose content is used as the actual data for the data sets
+that are dispatched to the daemon. How many such columns you need is determined
+by the B<Type> setting above. If you specify too many or not enough columns,
+the plugin will complain about that and no data will be submitted to the
+daemon.
+
+The actual data type in the columns is not that important. The plugin will
+automatically cast the values to the right type if it know how to do that. So
+it should be able to handle integer an floating point types, as well as strings
+(if they include a number at the beginning).
+
+There must be at least one B<ValuesFrom> option inside each B<Result> block.
+
+=back
+
+=head3 B<Database> blocks
+
+Database blocks define a connection to a database and which queries should be
+sent to that database. Since the used "dbi" library can handle a wide variety
+of databases, the configuration is very generic. If in doubt, refer to libdbi's
+documentationE<nbsp>- we stick as close to the terminology used there.
+
+Each database needs a "name" as string argument in the starting tag of the
+block. This name will be used as "PluginInstance" in the values submitted to
+the daemon. Other than that, that name is not used.
+
+=over 4
+
+=item B<Driver> I<Driver>
+
+Specifies the driver to use to connect to the database. In many cases those
+drivers are named after the database they can connect to, but this is not a
+technical necessity. These drivers are sometimes referred to as "DBD",
+B<D>ataB<B>ase B<D>river, and some distributions ship them in separate
+packages. Drivers for the "dbi" library are developed by the B<libdbi-drivers>
+project at L<http://libdbi-drivers.sourceforge.net/>.
+
+You need to give the driver name as expected by the "dbi" library here. You
+should be able to find that in the documentation for each driver. If you
+mistype the driver name, the plugin will dump a list of all known driver names
+to the log.
+
+=item B<DriverOption> I<Key> I<Value>
+
+Sets driver-specific options. What option a driver supports can be found in the
+documentation for each driver, somewhere at
+L<http://libdbi-drivers.sourceforge.net/>. However, the options "host",
+"username", "password", and "dbname" seem to be deE<nbsp>facto standards.
+
+Unfortunately, drivers are not too keen to report errors when an unknown option
+is passed to them, so invalid settings here may go unnoticed. This is not the
+plugin's fault, it will report errors if it gets them from the libraryE<nbsp>/
+the driver. If a driver complains about an option, the plugin will dump a
+complete list of all options understood by that driver to the log.
+
+=item B<SelectDB> I<Database>
+
+In some cases, the database name you connect with is not the database name you
+want to use for querying data. If this option is set, the plugin will "select"
+(switch to) that database after the connection is established.
+
+=item B<Query> I<QueryName>
+
+Associates the query named I<QueryName> with this database connection. The
+query needs to be defined I<before> this statement, i.E<nbsp>e. all query
+blocks you want to refer to must be placed above the database block you want to
+refer to them from.
+
+=back
+
=head2 Plugin C<df>
=over 4
C<m> (megabyte), C<g> (gigabyte), C<t> (terabyte), and C<p> (petabyte). Please
note that there are 1000 bytes in a kilobyte, not 1024.
+=item B<Recursive> I<true>|I<false>
+
+Controls whether or not to recurse into subdirectories. Enabled by default.
+
+=back
+
+=head2 Plugin C<filter_pcre>
+
+This plugin allows you to filter and rewrite value lists based on
+Perl-compatible regular expressions whose syntax and semantics are as close as
+possible to those of the Perl 5 language. See L<pcre(3)> for details.
+
+ <Plugin filter_pcre>
+ <RegEx>
+ Host "^mail\d+$"
+ Plugin "^tcpconns$"
+ TypeInstance "^SYN_"
+
+ Action NoWrite
+ </RegEx>
+
+ <RegEx>
+ Plugin "^sensors$"
+ PluginInstance "^Some Weird Sensor Chip Name Prefix"
+
+ SubstitutePluginInstance "foo"
+ </RegEx>
+ </Plugin>
+
+The configuration consists of one or more C<RegEx> blocks, each of which
+specifies a regular expression identifying a set of value lists and how to
+handle successful matches. A value list keeps the values of a single data-set
+and is identified by the tuple (host, plugin, plugin instance, type, type
+instance). The plugin and type instances are optional components. If they are
+missing they are treated as empty strings. Within those blocks, the following
+options are recognized:
+
+=over 4
+
+=item B<Host> I<regex>
+
+=item B<Plugin> I<regex>
+
+=item B<PluginInstance> I<regex>
+
+=item B<Type> I<regex>
+
+=item B<TypeInstance> I<regex>
+
+Specifies the regular expression for each component of the identifier. If any
+of these options is missing it is interpreted as a pattern which matches any
+string. All five components of a value list have to match the appropriate
+regular expression to trigger the specified action.
+
+=item B<Action> I<NoWrite>|I<NoThresholdCheck>|I<Ignore>
+
+Specify how to handle successful matches:
+
+=over 4
+
+=item B<NoWrite>
+
+Do not send the value list to any output (a.k.a. write) plugins.
+
+=item B<NoThresholdCheck>
+
+Skip threshold checking for this value list.
+
+=item B<Ignore>
+
+Completely ignore this value list.
+
+=back
+
+Two or more actions may be combined by specifying multiple B<Action> options.
+
+=item B<SubstituteHost> I<replacement>
+
+=item B<SubstitutePlugin> I<replacement>
+
+=item B<SubstitutePluginInstance> I<replacement>
+
+=item B<SubstituteType> I<replacement>
+
+=item B<SubstituteTypeInstance> I<replacement>
+
+Upon a successful match, the matching substring will be replaced by the
+specified I<replacement> text. These options require that an appropriate regex
+has been specified before, e.E<nbsp>g. B<SubstituteHost> requires that the
+B<Host> option has been specified before.
+
+B<Note>: It is not recommended to modify the type unless you really know what
+you are doing. The type is used to identify the data-set definition of the
+dispatched values.
+
=back
=head2 Plugin C<hddtemp>
connection is interrupted for whatever reason it will try to re-connect. The
plugin will complaint loudly in case anything goes wrong.
-This plugin issues C<SHOW STATUS> and evaluates C<Bytes_{received,sent}>,
-C<Com_*> and C<Handler_*> which correspond to F<mysql_octets.rrd>,
-F<mysql_commands-*.rrd> and F<mysql_handler-*.rrd>. Also, the values of
-C<Qcache_*> are put in F<mysql_qcache.rrd> and values of C<Threads_*> are put
-in F<mysql_threads.rrd>. Please refer to the B<MySQL reference manual>,
-I<5.2.4. Server Status Variables> for an explanation of these values.
+This plugin issues the MySQL C<SHOW STATUS> command and collects information
+about MySQL network traffic, executed statements, requests, the query cache
+and threads by evaluating the C<Bytes_{received,sent}>, C<Com_*>,
+C<Handler_*>, C<Qcache_*> and C<Threads_*> return values. Please refer to the
+B<MySQL reference manual>, I<5.1.6. Server Status Variables> for an
+explanation of these values.
Use the following options to configure the plugin:
=item B<User> I<Username>
-Username to use when connecting to the database.
+Username to use when connecting to the database. The user does not have to be
+granted any privileges (which is synonym to granting the C<USAGE> privilege).
+Any existing MySQL user will do.
=item B<Password> I<Password>
Select this database. Defaults to I<no database> which is a perfectly reasonable
option for what this plugin does.
+=item B<Port> I<Port>
+
+TCP-port to connect to. The port must be specified in its numeric form, but it
+must be passed as a string nonetheless. For example:
+
+ Port "3306"
+
+If B<Host> is set to B<localhost> (the default), this setting has no effect.
+See the documentation for the C<mysql_real_connect> function for details.
+
+=item B<Socket> I<Socket>
+
+Specifies the path to the UNIX domain socket of the MySQL server. This option
+only has any effect, if B<Host> is set to B<localhost> (the default).
+Otherwise, use the B<Port> option above. See the documentation for the
+C<mysql_real_connect> function for details.
+
=back
=head2 Plugin C<netlink>
or two, reading all values will take more than ten seconds (the default
interval). We will probably add some separate thread for reading the sensors
and some cache or something like that, but it's not done yet. We will try to
-maintain backwards compatibility in the future, but we can't probmise. So in
-short: If it works for you: Great! But kaap in mind that the config I<might>
+maintain backwards compatibility in the future, but we can't promise. So in
+short: If it works for you: Great! But keep in mind that the config I<might>
change, though this is unlikely. Oh, and if you want to help improving this
plugin, just send a short notice to the mailing list. ThanksE<nbsp>:)
+=head2 Plugin C<openvpn>
+
+The OpenVPN plugin reads a status file maintained by OpenVPN and gathers
+traffic statistics about connected clients.
+
+To set up OpenVPN to write to the status file periodically, use the
+B<--status> option of OpenVPN. Since OpenVPN can write two different formats,
+you need to set the required format, too. This is done by setting
+B<--status-version> to B<2>.
+
+So, in a nutshell you need:
+
+ openvpn $OTHER_OPTIONS \
+ --status "/var/run/openvpn-status" 10 \
+ --status-version 2
+
+Available options:
+
+=over 4
+
+=item B<StatusFile> I<File>
+
+Specifies the location of the status file.
+
+=back
+
+=head2 Plugin C<oracle>
+
+The "oracle" plugin uses the Oracle® Call Interface I<(OCI)> to connect to an
+Oracle® Database and lets you execute SQL statements there. It is very similar
+to the "dbi" plugin, because it was written around the same time. See the "dbi"
+plugin's documentation above for details.
+
+ <Plugin oracle>
+ <Query "out_of_stock">
+ Statement "SELECT category, COUNT(*) AS value FROM products WHERE in_stock = 0 GROUP BY category"
+ <Result>
+ Type "gauge"
+ InstancesFrom "category"
+ ValuesFrom "value"
+ </Result>
+ </Query>
+ <Database "product_information">
+ ConnectID "db01"
+ Username "oracle"
+ Password "secret"
+ Query "out_of_stock"
+ </Database>
+ </Plugin>
+
+=head3 B<Query> blocks
+
+The Query blocks are handled identically to the Query blocks of the "dbi"
+plugin. Please see its documentation above for details on how to specify
+queries.
+
+=head3 B<Database> blocks
+
+Database blocks define a connection to a database and which queries should be
+sent to that database. Each database needs a "name" as string argument in the
+starting tag of the block. This name will be used as "PluginInstance" in the
+values submitted to the daemon. Other than that, that name is not used.
+
+=over 4
+
+=item B<ConnectID> I<ID>
+
+Defines the "database alias" or "service name" to connect to. Usually, these
+names are defined in the file named C<$ORACLE_HOME/network/admin/tnsnames.ora>.
+
+=item B<Username> I<Username>
+
+Username used for authentication.
+
+=item B<Password> I<Password>
+
+Password used for authentication.
+
+=item B<Query> I<QueryName>
+
+Associates the query named I<QueryName> with this database connection. The
+query needs to be defined I<before> this statement, i.E<nbsp>e. all query
+blocks you want to refer to must be placed above the database block you want to
+refer to them from.
+
+=back
+
=head2 Plugin C<perl>
This plugin embeds a Perl-interpreter into collectd and provides an interface
<Plugin postgresql>
<Query magic>
- Query "SELECT magic, spells FROM wizard WHERE host = $1;"
+ Statement "SELECT magic, spells FROM wizard WHERE host = $1;"
Param hostname
Column gauge magic
Column counter spells
=over 4
-=item B<Query> I<sql query>
+=item B<Statement> I<sql query statement>
-Specify the I<sql query> which the plugin should execute. The string may
-contain the tokens B<$1>, B<$2>, etc. which are used to reference the first,
-second, etc. parameter. The value of the parameters is specified by the
+Specify the I<sql query statement> which the plugin should execute. The string
+may contain the tokens B<$1>, B<$2>, etc. which are used to reference the
+first, second, etc. parameter. The value of the parameters is specified by the
B<Param> configuration option - see below for details. To include a literal
B<$> character followed by a number, surround it with single quotes (B<'>).
allowed. Note, however, that only a single command may be used. Semicolons are
allowed as long as a single non-empty command has been specified only.
+=item B<Query> I<sql query statement>
+
+This is a deprecated synonym for B<Statement>. It will be removed in version 5
+of collectd.
+
=item B<Param> I<hostname>|I<database>|I<username>
Specify the parameters which should be passed to the SQL query. The parameters
=item B<Socket> I<Path>
Configures the path to the UNIX domain socket to be used when connecting to the
-daemon. By default C</var/run/pdns.controlsocket> will be used for an
-authoritative server and C</var/run/pdns_recursor.controlsocket> will be used
-for the recursor.
+daemon. By default C<${localstatedir}/run/pdns.controlsocket> will be used for
+an authoritative server and C<${localstatedir}/run/pdns_recursor.controlsocket>
+will be used for the recursor.
=back
(RSS), user- and system-time used, number of processes and number of threads,
and minor and major pagefaults.
+=item B<ProcessMatch> I<name> I<regex>
+
+Similar to the B<Process> option this allows to select more detailed
+statistics of processes matching the specified I<regex> (see L<regex(7)> for
+details). The statistics of all matching processes are summed up and
+dispatched to the daemon using the specified I<name> as an identifier. This
+allows to "group" several processes together. I<name> must not contain
+slashes.
+
+=back
+
+=head2 Plugin C<rrdcached>
+
+The C<rrdcached> plugin uses the RRDTool accelerator daemon, L<rrdcached(1)>,
+to store values to RRD files in an efficient manner. The combination of the
+C<rrdcached> B<plugin> and the C<rrdcached> B<daemon> is very similar to the
+way the C<rrdtool> plugin works (see below). The added abstraction layer
+provides a number of benefits, though: Because the cache is not within
+C<collectd> anymore, it does not need to be flushed when C<collectd> is to be
+restarted. This results in much shorter (if any) gaps in graphs, especially
+under heavy load. Also, the C<rrdtool> command line utility is aware of the
+daemon so that it can flush values to disk automatically when needed. This
+allows to integrate automated flushing of values into graphing solutions much
+more easily.
+
+There are disadvantages, though: The daemon may reside on a different host, so
+it may not be possible for C<collectd> to create the appropriate RRD files
+anymore. And even if C<rrdcached> runs on the same host, it may run in a
+different base directory, so relative paths may do weird stuff if you're not
+careful.
+
+So the B<recommended configuration> is to let C<collectd> and C<rrdcached> run
+on the same host, communicating via a UNIX domain socket. The B<DataDir>
+setting should be set to an absolute path, so that a changed base directory
+does not result in RRD files being createdE<nbsp>/ expected in the wrong place.
+
+=over 4
+
+=item B<DaemonAddress> I<Address>
+
+Address of the daemon as understood by the C<rrdc_connect> function of the RRD
+library. See L<rrdcached(1)> for details. Example:
+
+ <Plugin "rrdcached">
+ DaemonAddress "unix:/var/run/rrdcached.sock"
+ </Plugin>
+
+=item B<DataDir> I<Directory>
+
+Set the base directory in which the RRD files reside. If this is a relative
+path, it is relative to the working base directory of the C<rrdcached> daemon!
+Use of an absolute path is recommended.
+
+=item B<CreateFiles> B<true>|B<false>
+
+Enables or disables the creation of RRD files. If the daemon is not running
+locally, or B<DataDir> is set to a relative path, this will not work as
+expected. Default is B<true>.
+
=back
=head2 Plugin C<rrdtool>
will run serious performance problems. The B<CacheFlush> setting and the
internal update queue assert that collectd continues to work just fine even
under heavy load, but the system may become very unresponsive and slow. This is
-a problem especially if create graphs from the RRD files on the same machine,
-for example using the C<graph.cgi> script included in the
+a problem especially if you create graphs from the RRD files on the same
+machine, for example using the C<graph.cgi> script included in the
C<contrib/collection3/> directory.
This setting is designed for very large setups. Setting this option to a value
<File "/var/log/exim4/mainlog">
Instance "exim"
<Match>
- Regex "S=([1-9][0-9]*)"
- DSType "CounterAdd"
- Type "ipt_bytes"
- Instance "total"
+ Regex "S=([1-9][0-9]*)"
+ DSType "CounterAdd"
+ Type "ipt_bytes"
+ Instance "total"
</Match>
<Match>
- Regex "\\<R=local_user\\>"
- DSType "CounterInc"
- Type "counter"
- Instance "local_user"
+ Regex "\\<R=local_user\\>"
+ DSType "CounterInc"
+ Type "counter"
+ Instance "local_user"
</Match>
</File>
</Plugin>
will be dispatched after about 120 seconds. It may take a little longer because
the timeout is checked only once each B<Interval> on the server.
+When a value comes within range again or is received after it was missing, an
+"OKAY-notification" is dispatched.
+
Here is a configuration example to get you started. Read below for more
information.
<Plugin "memory">
<Type "memory">
Instance "cached"
- WarningMin 100000000
+ WarningMin 100000000
</Type>
</Plugin>
</Host>
=back
+=head1 FILTER CONFIGURATION
+
+TODO: Update this entire section once development is done.
+
+Starting with collectd 4.6 there is a powerful filtering infrastructure
+implemented in the daemon. The concept has mostly been copied from I<iptables>,
+the packet filter infrastructure for Linux. We'll use a similar terminology, so
+that users that are familiar with iptables feel right at home.
+
+=head2 Terminology
+
+The most important terms are:
+
+=over 4
+
+=item B<Match>
+
+A I<match> is a criteria to select specific values. Examples are, of course, the
+name of the value or it's current value.
+
+=item B<Target>
+
+A I<target> is some action that is to be performed with data. Such actions
+could, for example, be to change part of the value's identifier or to ignore
+the value completely. Built-in functions are B<write> and B<stop>, see below.
+
+Some targets, for example the built-in B<stop> target, signal that processing
+of a value should be stopped. In that case processing of the current chain will
+be aborted.
+
+=item B<Rule>
+
+The combination of any number of matches and at least one target is called a
+I<rule>. The target actions will be performed for all values for which B<all>
+matches apply. If the rule does not have any matches associated with it, the
+target action will be performed for all values.
+
+If any target returns the stop condition, the processing will stop right away.
+This means that any targets following the current one will not be called after
+the stop condition has been returned.
+
+=item B<Chain>
+
+A I<chain> is a list of rules and possibly default targets. The rules are tried
+in order and if one matches, the associated target will be called. If a value
+is handled by a rule, it depends on the target whether or not any subsequent
+rules are considered or if traversal of the chain is aborted. After all rules
+have been checked and no target returned the stop condition, the default
+targets will be executed.
+
+=back
+
+=head2 General structure
+
+The following shows the resulting structure:
+
+ +---------+
+ ! Chain !
+ +---------+
+ !
+ V
+ +---------+ +---------+ +---------+ +---------+
+ ! Rule !->! Match !->! Match !->! Target !
+ +---------+ +---------+ +---------+ +---------+
+ !
+ V
+ +---------+ +---------+ +---------+
+ ! Rule !->! Target !->! Target !
+ +---------+ +---------+ +---------+
+ !
+ V
+ :
+ :
+ !
+ V
+ +---------+ +---------+ +---------+
+ ! Rule !->! Match !->! Target !
+ +---------+ +---------+ +---------+
+ !
+ V
+ +---------+
+ ! Default !
+ ! Target !
+ +---------+
+
+=head2 Synopsis
+
+The configuration reflects this structure directly:
+
+ <Chain "main">
+ <Rule "ignore_mysql_show">
+ <Match "regex">
+ Plugin "^mysql$"
+ Type "^mysql_command$"
+ TypeInstance "^show_"
+ </Match>
+ <Target "stop">
+ </Target>
+ </Rule>
+ <Target "write">
+ Plugin "rrdtool"
+ </Target>
+ </Chain>
+
+The above configuration example will ignore all values where the plugin field
+is "mysql", the type is "mysql_command" and the type instance begins with
+"show_". All other values will be sent to the "rrdtool" write plugin via the
+default target of the chain.
+
+=head2 List of configuration options
+
+=over 4
+
+=item B<Chain> I<Name>
+
+Adds a new chain with a certain name. This name can be used to refer to a
+specific chain, for example to jump to it.
+
+Within the B<Chain> block, there can be B<Rule> blocks and B<Target> blocks.
+
+=item B<Rule> [I<Name>]
+
+Adds a new rule to the current chain. The name of the rule is optional and
+currently has no meaning for the daemon.
+
+Within the B<Rule> block, there may be any number of B<Match> blocks and there
+must be at least one B<Target> block.
+
+=item B<Match> I<Name>
+
+Adds a match to a B<Rule> block. The name specifies what kind of match should
+be performed. Available matches depend on the plugins that have been loaded.
+
+The arguments inside the B<Match> block are passed to the plugin implementing
+the match, so which arguments are valid here depends on the plugin being used.
+If you do not need any to pass any arguments to a match, you can use the
+shorter syntax:
+
+ Match "foobar"
+
+Which is equivalent to:
+
+ <Match "foobar">
+ </Match>
+
+=item B<Target> I<Name>
+
+Add a target to a rule or a default target to a chain. The name specifies what
+kind of target is to be added. Which targets are available depends on the
+plugins being loaded.
+
+The arguments inside the B<Target> block are passed to the plugin implementing
+the target, so which arguments are valid here depends on the plugin being used.
+If you do not need any to pass any arguments to a target, you can use the
+shorter syntax:
+
+ Target "stop"
+
+This is the same as writing:
+
+ <Target "stop">
+ </Target>
+
+=back
+
+=head2 Built-in targets
+
+The following targets are built into the core daemon and therefore need no
+plugins to be loaded:
+
+=over 4
+
+=item B<return>
+
+Signals the "return" condition. This causes the current chain to stop
+processing the value and returns control to the calling chain. The calling
+chain will continue processing targets and rules just after the B<jump> target
+(see below). This is very similar to the B<RETURN> target of iptables, see
+L<iptables(8)>.
+
+This target does not have any options.
+
+Example:
+
+ Target "return"
+
+=item B<stop>
+
+Signals the "stop" condition, causing processing of the value to be aborted
+immediately. This is similar to the B<DROP> target of iptables, see
+L<iptables(8)>.
+
+This target does not have any options.
+
+Example:
+
+ Target "stop"
+
+=item B<write>
+
+Sends the value to write plugins.
+
+Available options:
+
+=over 4
+
+=item B<Plugin> I<Name>
+
+Name of the write plugin to which the data should be sent. This option may be
+given multiple times to send the data to more than one write plugin.
+
+=back
+
+If no plugin is explicitly specified, the values will be sent to all available
+write plugins.
+
+Example:
+
+ <Target "write">
+ Plugin "rrdtool"
+ </Target>
+
+=item B<jump>
+
+Starts processing the rules of another chain. If the end of that chain is
+reached, or a stop condition is encountered, processing will continue right
+after the B<jump> target, i.E<nbsp>e. with the next target or the next rule.
+This is similar to the B<-j> command line option of iptables, see
+L<iptables(8)>.
+
+Available options:
+
+=over 4
+
+=item B<Chain> I<Name>
+
+Jumps to the chain I<Name>. This argument is required and may appear only once.
+
+=back
+
+Example:
+
+ <Target "jump">
+ Chain "foobar"
+ </Target>
+
+=back
+
+=head2 Available matches
+
+=over 4
+
+=item B<regex>
+
+Matches a value using regular expressions.
+
+Available options:
+
+=over 4
+
+=item B<Host> I<Regex>
+
+=item B<Plugin> I<Regex>
+
+=item B<PluginInstance> I<Regex>
+
+=item B<Type> I<Regex>
+
+=item B<TypeInstance> I<Regex>
+
+Match values where the given regular expressions match the various fields of
+the identifier of a value. If multiple regular expressions are given, B<all>
+regexen must match for a value to match.
+
+=back
+
+Example:
+
+ <Match "regex">
+ Host "customer[0-9]+"
+ Plugin "^foobar$"
+ </Match>
+
+=item B<value>
+
+Matches the actual value of data sources against given minimumE<nbsp>/ maximum
+values. If a data-set consists of more than one data-source, all data-sources
+must match the specified ranges for a positive match.
+
+Available options:
+
+=over 4
+
+=item B<Min> I<Value>
+
+Sets the smallest value which still results in a match. If unset, behaves like
+negative infinity.
+
+=item B<Max> I<Value>
+
+Sets the largest value which still results in a match. If unset, behaves like
+positive infinity.
+
+=item B<Invert> B<true>|B<false>
+
+Inverts the selection. If the B<Min> and B<Max> settings result in a match,
+no-match is returned and vice versa. Please note that the B<Invert> setting
+only effects how B<Min> and B<Max> are applied to a specific value. Especially
+the B<DataSource> and B<Satisfy> settings (see below) are not inverted.
+
+=item B<DataSource> I<DSName> [I<DSName> ...]
+
+Select one or more of the data sources. If no data source is configured, all
+data sources will be checked. If the type handled by the match does not have a
+data source of the specified name(s), this will always result in no match
+(independent of the B<Invert> setting).
+
+=item B<Satisfy> B<Any>|B<All>
+
+Specifies how checking with several data sources is performed. If set to
+B<Any>, the match succeeds if one of the data sources is in the configured
+range. If set to B<All> the match only succeeds if all data sources are within
+the configured range. Default is B<All>.
+
+Usually B<All> is used for positive matches, B<Any> is used for negative
+matches. This means that with B<All> you usually check that all values are in a
+"good" range, while with B<Any> you check if any value is within a "bad" range
+(or outside the "good" range).
+
+=back
+
+Either B<Min> or B<Max>, but not both, may be unset.
+
+Example:
+
+ # Match all values smaller than or equal to 100. Matches only if all data
+ # sources are below 100.
+ <Match "value">
+ Max 100
+ Satisfy "All"
+ </Match>
+
+ # Match if the value of any data source is outside the range of 0 - 100.
+ <Match "value">
+ Min 0
+ Max 100
+ Invert true
+ Satisfy "Any"
+ </Match>
+
+=back
+
+=head2 Available targets
+
+=over 4
+
+=item B<notification>
+
+Creates and dispatches a notification.
+
+Available options:
+
+=over 4
+
+=item B<Message> I<String>
+
+This required option sets the message of the notification. The following
+placeholders will be replaced by an appropriate value:
+
+=over 4
+
+=item B<%{host}>
+
+=item B<%{plugin}>
+
+=item B<%{plugin_instance}>
+
+=item B<%{type}>
+
+=item B<%{type_instance}>
+
+These placeholders are replaced by the identifier field of the same name.
+
+=item B<%{ds:>I<name>B<}>
+
+These placeholders are replaced by a (hopefully) human readable representation
+of the current rate of this data source. If you changed the instance name
+(using the B<set> or B<replace> targets, see below), it may not be possible to
+convert counter values to rates.
+
+=back
+
+Please note that these placeholders are B<case sensitive>!
+
+=item B<Severity> B<"FATAL">|B<"WARNING">|B<"OKAY">
+
+Sets the severity of the message. If omitted, the severity B<"WARNING"> is
+used.
+
+=back
+
+Example:
+
+ <Target "notification">
+ Message "Oops, the %{type_instance} temperature is currently %{ds:value}!"
+ Severity "WARNING"
+ </Target>
+
+=item B<replace>
+
+Replaces parts of the identifier using regular expressions.
+
+Available options:
+
+=over 4
+
+=item B<Host> I<Regex> I<Replacement>
+
+=item B<Plugin> I<Regex> I<Replacement>
+
+=item B<PluginInstance> I<Regex> I<Replacement>
+
+=item B<TypeInstance> I<Regex> I<Replacement>
+
+Match the appropriate field with the given regular expression I<Regex>. If the
+regular expression matches, that part that matches is replaced with
+I<Replacement>. If multiple places of the input buffer match a given regular
+expression, only the first occurrence will be replaced.
+
+You can specify each option multiple times to use multiple regular expressions
+one after another.
+
+=back
+
+Example:
+
+ <Target "replace">
+ # Replace "example.net" with "example.com"
+ Host "\\<example.net\\>" "example.com"
+
+ # Strip "www." from hostnames
+ Host "\\<www\\." ""
+ </Target>
+
+=item B<set>
+
+Sets part of the identifier of a value to a given string.
+
+Available options:
+
+=over 4
+
+=item B<Host> I<String>
+
+=item B<Plugin> I<String>
+
+=item B<PluginInstance> I<String>
+
+=item B<TypeInstance> I<String>
+
+Set the appropriate field to the given string. The strings for plugin instance
+and type instance may be empty, the strings for host and plugin may not be
+empty. It's currently not possible to set the type of a value this way.
+
+=back
+
+Example:
+
+ <Target "set">
+ PluginInstance "coretemp"
+ TypeInstance "core3"
+ </Target>
+
+=back
+
+=head2 Backwards compatibility
+
+If you use collectd with an old configuration, i.E<nbsp>e. one without a
+B<Chain> block, it will behave as it used to. This is equivalent to the
+following configuration:
+
+ <Chain "main">
+ Target "write"
+ </Chain>
+
+If you specify a B<Chain> block anywhere, the B<write> target will not be added
+anywhere and you will have to make sure that it is called where appropriate. We
+suggest to add the above snippet as default target to your main chain.
+
+TODO: Notifications will be implemented using chains, too. Describe that here!
+
+=head2 Examples
+
+Ignore all values, where the hostname does not contain a dot, i.E<nbsp>e. can't
+be an FQDN.
+
+ <Chain "main">
+ <Rule "no_fqdn">
+ <Match "regex">
+ Host "^[^\.]*$"
+ </Match>
+ Target "stop"
+ </Rule>
+ Target "write"
+ </Chain>
+
=head1 SEE ALSO
L<collectd(1)>,
L<collectd-unixsock(5)>,
L<types.db(5)>,
L<hddtemp(8)>,
+L<iptables(8)>,
L<kstat(3KSTAT)>,
L<mbmon(1)>,
+L<pcre(3)>,
L<psql(1)>,
+L<regex(7)>,
L<rrdtool(1)>,
L<sensors(1)>
projects / collectd.git / blobdiff