ignored. Values are either string, enclosed in double-quotes,
(floating-point-)numbers or a boolean expression, i.E<nbsp>e. either B<true> or
B<false>. String containing of only alphanumeric characters and underscores do
-not need to be quoted.
+not need to be quoted. Lines may be wrapped by using `\' as the last character
+before the newline. This allows long lines to be split into multiple lines.
+Quoted strings may be wrapped as well. However, those are treated special in
+that whitespace at the beginning of the following lines will be ignored, which
+allows for nicely indenting the wrapped lines.
The configuration is read and processed in order, i.E<nbsp>e. from top to
bottom. So the plugins are loaded in the order listed in this config file. It
Optional password needed for authentication.
+=item B<VerifyPeer> B<true|false>
+
+Enable or disable peer SSL certificate verification. See
+L<http://curl.haxx.se/docs/sslcerts.html> for details. Enabled by default.
+
+=item B<VerifyHost> B<true|false>
+
+Enable or disable peer host name verification. If enabled, the plugin checks
+if the C<Common Name> or a C<Subject Alternate Name> field of the SSL
+certificate matches the host name provided by the B<URL> option. If this
+identity check fails, the connection is aborted. Obviously, only works when
+connecting to a SSL enabled server. Enabled by default.
+
=item B<CACert> I<File>
File that holds one or more SSL certificates. If you want to use HTTPS you will
=back
+=head2 Plugin C<dbi>
+
+This plugin uses the "B<dbi>" library (L<http://libdbi.sourceforge.net/>) to
+connect to various databases, execute SQL statements and read back the results.
+You can configure how each column is to be interpreted and the plugin will
+generate one data set 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"
+ Type "gauge"
+ InstancesFrom "category"
+ ValuesFrom "value"
+ </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 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 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.
+
+=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.
+
+=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.
+
+=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).
+
+=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
=back
+=head2 Plugin C<filecount>
+
+The C<filecount> plugin counts the number of files in a certain directory (and
+its subdirectories) and their combined size. The configuration is very straight
+forward:
+
+ <Plugin "filecount">
+ <Directory "/var/qmail/queue/mess">
+ Instance "qmail-message"
+ </Directory>
+ <Directory "/var/qmail/queue/todo">
+ Instance "qmail-todo"
+ </Directory>
+ <Directory "/var/lib/php5">
+ Instance "php5-sessions"
+ Name "sess_*"
+ </Directory>
+ </Plugin>
+
+The example above counts the number of files in QMail's queue directories and
+the number of PHP5 sessions. Jfiy: The "todo" queue holds the messages that
+QMail has not yet looked at, the "message" queue holds the messages that were
+classified into "local" and "remote".
+
+As you can see, the configuration consists of one or more C<Directory> blocks,
+each of which specifies a directory in which to count the files. Within those
+blocks, the following options are recognized:
+
+=over 4
+
+=item B<Instance> I<Instance>
+
+Sets the plugin instance to I<Instance>. That instance name must be unique, but
+it's your responsibility, the plugin doesn't check for that. If not given, the
+instance is set to the directory name with all slashes replaced by underscores
+and all leading underscores removed.
+
+=item B<Name> I<Pattern>
+
+Only count files that match I<Pattern>, where I<Pattern> is a shell-like
+wildcard as understood by L<fnmatch(3)>. Only the B<filename> is checked
+against the pattern, not the entire path. In case this makes it easier for you:
+This option has been named after the B<-name> parameter to L<find(1)>.
+
+=item B<MTime> I<Age>
+
+Count only files of a specific age: If I<Age> is greater than zero, only files
+that haven't been touched in the last I<Age> seconds are counted. If I<Age> is
+a negative number, this is inversed. For example, if B<-60> is specified, only
+files that have been modified in the last minute will be counted.
+
+The number can also be followed by a "multiplier" to easily specify a larger
+timespan. When given in this notation, the argument must in quoted, i.E<nbsp>e.
+must be passed as string. So the B<-60> could also be written as B<"-1m"> (one
+minute). Valid multipliers are C<s> (second), C<m> (minute), C<h> (hour), C<d>
+(day), C<w> (week), and C<y> (year). There is no "month" multiplier. You can
+also specify fractional numbers, e.E<nbsp>g. B<"0.5d"> is identical to
+B<"12h">.
+
+=item B<Size> I<Size>
+
+Count only files of a specific size. When I<Size> is a positive number, only
+files that are at least this big are counted. If I<Size> is a negative number,
+this is inversed, i.E<nbsp>e. only files smaller than the absolute value of
+I<Size> are counted.
+
+As with the B<MTime> option, a "multiplier" may be added. For a detailed
+description see above. Valid multipliers here are C<b> (byte), C<k> (kilobyte),
+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>
To get values from B<hddtemp> collectd connects to B<localhost> (127.0.0.1),
interfaces you're interested in. Sometimes, however, it's easier/preferred
to collect all interfaces I<except> a few ones. This option enables you to
do that: By setting B<IgnoreSelected> to I<true> the effect of
-B<Interface> is inversed: All selected interfaces are ignored and all
+B<Interface> is inverted: All selected interfaces are ignored and all
other interfaces are collected.
=back
the effect of B<Sensor> is inverted: All selected sensors are ignored and
all other sensors are collected.
+=item B<NotifySensorAdd> I<true>|I<false>
+
+If a sensor appears after initialization time of a minute a notification
+is sent.
+
+=item B<NotifySensorRemove> I<true>|I<false>
+
+If a sensor disappears a notification is sent.
+
+=item B<NotifySensorNotPresent> I<true>|I<false>
+
+If you have for example dual power supply and one of them is (un)plugged then
+a notification is sent.
+
=back
=head2 Plugin C<iptables>
can use the B<Irq>-option to pick the interrupt you're interested in.
Sometimes, however, it's easier/preferred to collect all interrupts I<except> a
few ones. This option enables you to do that: By setting B<IgnoreSelected> to
-I<true> the effect of B<Irq> is inversed: All selected interrupts are ignored
+I<true> the effect of B<Irq> is inverted: All selected interrupts are ignored
and all other interrupts are collected.
=back
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>
The behaviour is the same as with all other similar plugins: If nothing is
selected at all, everything is collected. If some things are selected using the
options described above, only these statistics are collected. If you set
-B<IgnoreSelected> to B<true>, this behavior is inversed, i.E<nbsp>e. the
+B<IgnoreSelected> to B<true>, this behavior is inverted, i.E<nbsp>e. the
specified statistics will not be collected.
=back
=back
+=head2 Plugin C<notify_desktop>
+
+This plugin sends a desktop notification to a notification daemon, as defined
+in the Desktop Notification Specification. To actually display the
+notifications, B<notification-daemon> is required and B<collectd> has to be
+able to access the X server.
+
+The Desktop Notification Specification can be found at
+L<http://www.galago-project.org/specs/notification/>.
+
+=over 4
+
+=item B<OkayTimeout> I<timeout>
+
+=item B<WarningTimeout> I<timeout>
+
+=item B<FailureTimeout> I<timeout>
+
+Set the I<timeout>, in milliseconds, after which to expire the notification
+for C<OKAY>, C<WARNING> and C<FAILURE> severities respectively. If zero has
+been specified, the displayed notification will not be closed at all - the
+user has to do so herself. These options default to 5000. If a negative number
+has been specified, the default is used as well.
+
+=back
+
=head2 Plugin C<ntpd>
=over 4
=back
+=head2 Plugin C<onewire>
+
+B<EXPERIMENTAL!> See notes below.
+
+The C<onewire> plugin uses the B<owcapi> library from the B<owfs> project
+L<http://owfs.org/> to read sensors connected via the onewire bus.
+
+Currently only temperature sensors (sensors with the family code C<10>,
+e.E<nbsp>g. DS1820, DS18S20, DS1920) can be read. If you have other sensors you
+would like to have included, please send a sort request to the mailing list.
+
+Hubs (the DS2409 chips) are working, but read the note, why this plugin is
+experimental, below.
+
+=over 4
+
+=item B<Device> I<Device>
+
+Sets the device to read the values from. This can either be a "real" hardware
+device, such as a serial port or an USB port, or the address of the
+L<owserver(1)> socket, usually B<localhost:4304>.
+
+Though the documentation claims to automatically recognize the given address
+format, with versionE<nbsp>2.7p4 we had to specify the type explicitly. So
+with that version, the following configuration worked for us:
+
+ <Plugin onewire>
+ Device "-s localhost:4304"
+ </Plugin>
+
+This directive is B<required> and does not have a default value.
+
+=item B<Sensor> I<Sensor>
+
+Selects sensors to collect or to ignore, depending on B<IgnoreSelected>, see
+below. Sensors are specified without the family byte at the beginning, to you'd
+use C<F10FCA000800>, and B<not> include the leading C<10.> family byte and
+point.
+
+=item B<IgnoreSelected> I<true>|I<false>
+
+If no configuration if given, the B<onewire> plugin will collect data from all
+sensors found. This may not be practical, especially if sensors are added and
+removed regularly. Sometimes, however, it's easier/preferred to collect only
+specific sensors or all sensors I<except> a few specified ones. This option
+enables you to do that: By setting B<IgnoreSelected> to I<true> the effect of
+B<Sensor> is inverted: All selected interfaces are ignored and all other
+interfaces are collected.
+
+=back
+
+B<EXPERIMENTAL!> The C<onewire> plugin is experimental, because it doesn't yet
+work with big setups. It works with one sensor being attached to one
+controller, but as soon as you throw in a couple more senors and maybe a hub
+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>
+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<oracle>
+
+The "oracle" plugin uses the Oracle® Call Interface (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"
+ Type "gauge"
+ InstancesFrom "category"
+ ValuesFrom "value"
+ </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
=back
+=head2 Plugin C<postgresql>
+
+The C<postgresql> plugin queries statistics from PostgreSQL databases. It
+keeps a persistent connection to all configured databases and tries to
+reconnect if the connection has been interrupted. A database is configured by
+specifying a B<Database> block as described below. The default statistics are
+collected from PostgreSQL's B<statistics collector> which thus has to be
+enabled for this plugin to work correctly. This should usually be the case by
+default. See the section "The Statistics Collector" of the B<PostgreSQL
+Documentation> for details.
+
+By specifying custom database queries using a B<Query> block as described
+below, you may collect any data that is available from some PostgreSQL
+database. This way, you are able to access statistics of external daemons
+which are available in a PostgreSQL database or use future or special
+statistics provided by PostgreSQL without the need to upgrade your collectd
+installation.
+
+The B<PostgreSQL Documentation> manual can be found at
+L<http://www.postgresql.org/docs/manuals/>.
+
+ <Plugin postgresql>
+ <Query magic>
+ Query "SELECT magic, spells FROM wizard WHERE host = $1;"
+ Param hostname
+ Column gauge magic
+ Column counter spells
+ </Query>
+
+ <Database foo>
+ Host "hostname"
+ Port "5432"
+ User "username"
+ Password "secret"
+ SSLMode "prefer"
+ KRBSrvName "kerberos_service_name"
+ Query magic
+ </Database>
+ <Database bar>
+ Service "service_name"
+ </Database>
+ </Plugin>
+
+The B<Query> block defines one database query which may later be used by a
+database definition. It accepts a single mandatory argument which specifies
+the name of the query. The names of all queries have to be unique. The
+following configuration options are available to define the query:
+
+=over 4
+
+=item B<Query> I<sql query>
+
+Specify the I<sql query> which the plugin should execute. The string may
+contain the tokens B<$1>, B<$2>, etc. which are used to reference the first,
+second, etc. parameter. The value of the parameters is specified by the
+B<Param> configuration option - see below for details. To include a literal
+B<$> character followed by a number, surround it with single quotes (B<'>).
+
+Any SQL command which may return data (such as C<SELECT> or C<SHOW>) is
+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<Param> I<hostname>|I<database>|I<username>
+
+Specify the parameters which should be passed to the SQL query. The parameters
+are referred to in the SQL query as B<$1>, B<$2>, etc. in the same order as
+they appear in the configuration file. The value of the parameter is
+determined depending on the value of the B<Param> option as follows:
+
+=over 4
+
+=item I<hostname>
+
+The configured hostname of the database connection. If a UNIX domain socket is
+used, the parameter expands to "localhost".
+
+=item I<database>
+
+The name of the database of the current connection.
+
+=item I<username>
+
+The username used to connect to the database.
+
+=back
+
+Please note that parameters are only supported by PostgreSQL's protocol
+version 3 and above which was introduced in version 7.4 of PostgreSQL.
+
+=item B<Column> I<type> [I<type instance>]
+
+Specify the I<type> and optional I<type instance> used to dispatch the value
+of each result column. Detailed information about types and their
+configuration can be found in L<types.db(5)>. The number and order of the
+B<Column> options has to match the columns of the query result.
+
+=item B<MinPGVersion> I<version>
+
+=item B<MaxPGVersion> I<version>
+
+Specify the minimum or maximum version of PostgreSQL that this query should be
+used with. Some statistics might only be available with certain versions of
+PostgreSQL. This allows you to specify multiple queries with the same name but
+which apply to different versions, thus allowing you to use the same
+configuration in a heterogeneous environment.
+
+The I<version> has to be specified as the concatenation of the major, minor
+and patch-level versions, each represented as two-decimal-digit numbers. For
+example, version 8.2.3 will become 80203.
+
+=back
+
+The following predefined queries are available (the definitions can be found
+in the F<postgresql_default.conf> file which, by default, is available at
+C<I<prefix>/share/collectd/>):
+
+=over 4
+
+=item B<backends>
+
+This query collects the number of backends, i.E<nbsp>e. the number of
+connected clients.
+
+=item B<transactions>
+
+This query collects the numbers of committed and rolled-back transactions of
+the user tables.
+
+=item B<queries>
+
+This query collects the numbers of various table modifications (i.E<nbsp>e.
+insertions, updates, deletions) of the user tables.
+
+=item B<query_plans>
+
+This query collects the numbers of various table scans and returned tuples of
+the user tables.
+
+=item B<table_states>
+
+This query collects the numbers of live and dead rows in the user tables.
+
+=item B<disk_io>
+
+This query collects disk block access counts for user tables.
+
+=item B<disk_usage>
+
+This query collects the on-disk size of the database in bytes.
+
+=back
+
+The B<Database> block defines one PostgreSQL database for which to collect
+statistics. It accepts a single mandatory argument which specifies the
+database name. None of the other options are required. PostgreSQL will use
+default values as documented in the section "CONNECTING TO A DATABASE" in the
+L<psql(1)> manpage. However, be aware that those defaults may be influenced by
+the user collectd is run as and special environment variables. See the manpage
+for details.
+
+=over 4
+
+=item B<Host> I<hostname>
+
+Specify the hostname or IP of the PostgreSQL server to connect to. If the
+value begins with a slash, it is interpreted as the directory name in which to
+look for the UNIX domain socket.
+
+This option is also used to determine the hostname that is associated with a
+collected data set. If it has been omitted or either begins with with a slash
+or equals B<localhost> it will be replaced with the global hostname definition
+of collectd. Any other value will be passed literally to collectd when
+dispatching values. Also see the global B<Hostname> and B<FQDNLookup> options.
+
+=item B<Port> I<port>
+
+Specify the TCP port or the local UNIX domain socket file extension of the
+server.
+
+=item B<User> I<username>
+
+Specify the username to be used when connecting to the server.
+
+=item B<Password> I<password>
+
+Specify the password to be used when connecting to the server.
+
+=item B<SSLMode> I<disable>|I<allow>|I<prefer>|I<require>
+
+Specify whether to use an SSL connection when contacting the server. The
+following modes are supported:
+
+=over 4
+
+=item I<disable>
+
+Do not use SSL at all.
+
+=item I<allow>
+
+First, try to connect without using SSL. If that fails, try using SSL.
+
+=item I<prefer> (default)
+
+First, try to connect using SSL. If that fails, try without using SSL.
+
+=item I<require>
+
+Use SSL only.
+
+=back
+
+=item B<KRBSrvName> I<kerberos_service_name>
+
+Specify the Kerberos service name to use when authenticating with Kerberos 5
+or GSSAPI. See the sections "Kerberos authentication" and "GSSAPI" of the
+B<PostgreSQL Documentation> for details.
+
+=item B<Service> I<service_name>
+
+Specify the PostgreSQL service name to use for additional parameters. That
+service has to be defined in F<pg_service.conf> and holds additional
+connection parameters. See the section "The Connection Service File" in the
+B<PostgreSQL Documentation> for details.
+
+=item B<Query> I<query>
+
+Specify a I<query> which should be executed for the database connection. This
+may be any of the predefined or user-defined queries. If no such option is
+given, it defaults to "backends", "transactions", "queries", "query_plans",
+"table_states", "disk_io" and "disk_usage". Else, the specified queries are
+used only.
+
+=back
+
=head2 Plugin C<powerdns>
The C<powerdns> plugin queries statistics from an authoritative PowerDNS
(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>
=item B<CacheFlush> I<Seconds>
-When the C<rrdtool plugin> uses a cache (by setting B<CacheTimeout>, see below)
+When the C<rrdtool> plugin uses a cache (by setting B<CacheTimeout>, see below)
it writes all values for a certain RRD-file if the oldest value is older than
(or equal to) the number of seconds specified. If some RRD-file is not updated
anymore for some reason (the computer was shut down, the network is broken,
The trade off is that the graphs kind of "drag behind" and that more memory is
used.
+=item B<WritesPerSecond> B<Updates>
+
+When collecting many statistics with collectd and the C<rrdtool> plugin, you
+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 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
+between 25 and 80 updates per second, depending on your hardware, will leave
+the server responsive enough to draw graphs even while all the cached values
+are written to disk. Flushed values, i.E<nbsp>e. values that are forced to disk
+by the B<FLUSH> command, are B<not> effected by this limit. They are still
+written as fast as possible, so that web frontends have up to date data when
+generating graphs.
+
+For example: If you have 100,000 RRD files and set B<WritesPerSecond> to 30
+updates per second, writing all values to disk will take approximately
+56E<nbsp>minutes. Together with the flushing ability that's integrated into
+"collection3" you'll end up with a responsive and fast system, up to date
+graphs and basically a "backup" of your values every hour.
+
=back
=head2 Plugin C<sensors>
Thus, you can use the B<Sensor>-option to pick the sensors you're interested
in. Sometimes, however, it's easier/preferred to collect all sensors I<except> a
few ones. This option enables you to do that: By setting B<IgnoreSelected> to
-I<true> the effect of B<Sensor> is inversed: All selected sensors are ignored
+I<true> the effect of B<Sensor> is inverted: All selected sensors are ignored
and all other sensors are collected.
=back
<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>
=back
+=head2 Plugin C<thermal>
+
+=over 4
+
+=item B<ForceUseProcfs> I<true>|I<false>
+
+By default, the C<thermal> plugin tries to read the statistics from the Linux
+C<sysfs> interface. If that is not available, the plugin falls back to the
+C<procfs> interface. By setting this option to I<true>, you can force the
+plugin to use the latter. This option defaults to I<false>.
+
+=item B<Device> I<Device>
+
+Selects the name of the thermal device that you want to collect or ignore,
+depending on the value of the B<IgnoreSelected> option. This option may be
+used multiple times to specify a list of devices.
+
+=item B<IgnoreSelected> I<true>|I<false>
+
+Invert the selection: If set to true, all devices B<except> the ones that
+match the device names specified by the B<Device> option are collected. By
+default only selected devices are collected if a selection is made. If no
+selection is configured at all, B<all> devices are selected.
+
+=back
+
=head2 Plugin C<unixsock>
=over 4
<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.
+
+=back
+
+Either B<Min> or B<Max>, but not both, may be unset.
+
+Example:
+
+ # Match all values smaller than or equal to 100.
+ <Match "value">
+ Max 100
+ </Match>
+
+=back
+
+=head2 Available targets
+
+=over 4
+
+=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