=head1 NAME

collectd.conf - Configuration for the system statistics collection daemon B<collectd>

=head1 SYNOPSIS

  Mode    Client
  DataDir /path/to/data/
  PIDFile /path/to/pidfile/collectd.pid
  LogFile /path/to/logfile/collectd.log
  Server  123.123.123.123
  Port    12345

  LoadPlugin cpu
  LoadPlugin load
  LoadPlugin ping

  <Plugin ping>
    Host example.org
    Host provider.net
  </Plugin>

=head1 DESCRIPTION

This config file controls how the system statistics collection daemon
B<collectd> behaves. The most significant options are B<Mode>, which controlls
if the daemon will act as client, server or will be independent in local mode,
and B<LoadPlugin> which controls which plugins to load.

The syntax of this config file is similar to the config file of the famos
B<Apache Webserver>. Each line containes either a key-value-pair or a
section-start or -end. Empty lines and everything after the hash-symbol `#' is
ignored.

=head1 GLOBAL OPTIONS

=over 4

=item B<Mode> (B<Local>|B<Client>|B<Server>|B<Log>)

Sets the operating mode. See the section B<MODES> in L<collectd(1)> for a
description. This option determines which other options are allowed. Defaults
to B<Local>.

=item B<LoadPlugin> I<Plugin>

Loads the plugin I<Plugin>. There must be at least one such line or B<collectd>
will be mostly useless. The names of the plugins are listed in L<collectd(1)>.

=item B<PIDFile> I<File>

Sets where to write the PID file to. This file is overwritten when it exists
and deleted when the program ist stopped. Available in B<all modes>.

=item B<DataDir> I<Directory>

Sets the data directory. This is the directory beneath all RRD-files are
created. Possibly more subdirectories are created. This is also the working
directory for the daemon. Available in B<all modes>, though the B<Client> mode
won't write to this directory.

=item B<LogFile> I<File>

Sets the file to write debugging output to. This is only used if compiled with
debugging enabled. It's ignored otherwise. Available in B<all modes>.

=item B<Listen> I<Host> [I<Port>]

=item B<Server> I<Host> [I<Port>]

In B<client mode> the B<Server> statement sets the server to send datagrams to.
The statement may occur multiple times to send each datagram to multiple
destinations.

In B<server mode> the B<Listen> statement sets the interfaces to bind to. When
multiple statements are found the daemon will bind to multiple interfaces.

The argument I<Host> may be a hostname, an IPv4 address or an IPv6 address. If
the argument is a multicast address the daemon will join that multicast group.

If no B<Listen> statement is found the server tries join both, the IPv6
multicast group and the IPv4 multicast group. If no B<Server> statement is
found the client will try to send data to the IPv6 multicast group first. If
that failes the client will try the IPv4 multicast group.

The default IPv6 multicast group is C<ff18::efc0:4a42>. The default IPv4
multicast group is C<239.192.74.66>.

The optional I<Port> argument sets the port to use. It can either be given
using a numeric port number or a service name. If the argument is omited the
default port B<25826> is assumed.

=item B<TimeToLive> I<1-255>

Set the time-to-live of sent packets. This applies to all, unicast and
multicast, and IPv4 and IPv6 packets. The default is to not change this value.
That means that multicast packets will be sent with a TTL of C<1> (one) on most
operating systems.

=back

=head1 PLUGIN OPTIONS

Some Plugins may register own options. These options must be inclosed in a
C<Plugin>-Section. Which options exist depends on the plugin used:

=head2 Plugin C<apache>

To configure the C<apache>-plugin you first need to configure the Apache
webserver correctly. The Apache-plugin C<mod_status> needs to be loaded and
working and the C<ExtendedStatus> directive needs to be B<enabled>. You can use
the following snipped to base your Apache config upon:

  ExtendedStatus on
  <IfModule mod_status.c>
    <Location /mod_status>
      SetHandler server-status
    </Location>
  </IfModule>

The following options are accepted by the C<apache>-plugin:

=over 4

=item B<URL> I<http://host/mod_status?auto>

Sets the URL of the C<mod_status> output. This needs to be the output generated
by C<ExtendedStatus on> and it needs to be the machine readable output
generated by appending the C<?auto> argument.

=item B<User> I<Username>

Optional user name needed for authentication.

=item B<Password> I<Password>

Optional password needed for authentication.

=item B<CACert> I<File>

File that holds one or more SSL certificates. If you want to use HTTPS you will
possibly need this option. What CA certificates come bundeled with C<libcurl>
and are checked by default depends on the distribution you use.

=back

=head2 Plugin C<apcups>

=over 4

=item B<Host> I<Hostname>

Hostname of the host running B<apcupsd>. Defaults to B<localhost>. Please note
that IPv6 support has been disabled unless someone can confirm or decline that
B<apcupsd> can handle it.

=item B<Port> I<Port>

TCP-Port to connect to. Defaults to B<3551>.

=back

=head2 Plugin C<hddtemp>

=over 4

=item B<Host> I<Hostname>

Hostname to connect to. Defaults to B<127.0.0.1>.

=item B<Port> I<Port>

TCP-Port to connect to. Defaults to B<7634>.

=back

=head2 Plugin C<ntpd>

=over 4

=item B<Host> I<Hostname>

Hostname of the host running B<ntpd>. Defaults to B<localhost>.

=item B<Port> I<Port>

UDP-Port to connect to. Defaults to B<123>.

=back

=head2 Plugin C<mysql>

=over 4

=item B<Host> I<Hostname>

Hostname of the database server. Defaults to B<localhost>.

=item B<User> I<Username>

Username to use when connecting to the database.

=item B<Password> I<Password>

Password needed to log into the database.

=item B<Database> I<Database>

Select this database. Defaults to I<no database> which is a perfecly reasonable
option for what this plugin does.

=back

=head2 Plugin C<ping>

=over 4

=item B<Host> I<IP-address>

Host to ping periodically. This option may be repeated several times to ping
multiple hosts.

=item B<TTL> I<0-255>

Sets the Time-To-Live of generated ICMP packets.

=back

=head2 Plugin C<traffic>

=over 4

=item B<Interface> I<Interface>

Select this interface. By default these interfaces will then be collected. For a more detailed description see B<IgnoreSelected> below.

=item B<IgnoreSelected> I<true>|I<false>

If no configuration if given, the B<traffic>-plugin will collect data from
all interfaces. This may not be practical, especially for loopback- and
similar interfaces. Thus, you can use the B<Interface>-option to pick the
interfaces you're interested in. Sometimes, however, it's easier/prefered
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
other interfaces are collected.

=back

=head1 SEE ALSO

L<collectd(1)>

=head1 AUTHOR

Florian Forster E<lt>octo@verplant.orgE<gt>

=cut