=item
+Apache server stats (I<apache>)
+
+=item
+
+Apple hardware sensors (I<apple_sensors>, Darwin only)
+
+=item
+
Battery status (I<battery>)
=item
System ressources used by VServers (I<vserver>)
+=item
+
+Wireless network stats (I<wireless>)
+
=back
=head1 OPTIONS
written in RRD files that reside in I<DataDir>. This is the default mode when
collectd is linked against C<librrd>.
-The other two modes, B<client mode> and B<server mode>, are used to send data
-over a network and receive it again.
+The other modes, B<client mode> and B<server mode>, are used to send data over
+a network and receive it again.
-In B<client mode> the daemon collectd the data locally and send it's result to
-one or more network addresses. No RRD files are written in this case. This is
-the only mode available if collectd is not linked against C<librrd>.
+In B<client mode> the daemon collects the data locally and sends its results
+to one or more network addresses. No RRD files are written in this case. This
+is the only mode available if collectd is not linked against C<librrd>.
If started in B<server mode> the daemon will listen on one or more interfaces
and write the data it receives to RRD files. No data is collected locally.
+In the last mode, B<log mode>, data is collected locally and written in
+text files that reside in I<DataDir>.
+
Please refer to L<collectd.conf(5)> for the configuration options and default
values.
=head1 SPECIAL PLUGINS
+=head2 apache
+
+This module connects to an Apache webserver and expects the output produced by
+B<mod_status.c>. If requires B<libcurl> to set up the HTTP connection and issue
+the request(s). The following is a sample config for the Apache webserver. The
+use of C<ExtendedStatus on> is mandatory.
+
+ ExtendedStatus on
+ <IfModule mod_status.c>
+ <Location /mod_status>
+ SetHandler server-status
+ </Location>
+ </IfModule>
+
+This plugin requires further configuration. Please read L<collectd.conf(5)>.
+
=head2 cpufreq
This module reads F</sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq> (for
the first CPU installed) to get the current CPU frequency. If this file does
not exist make sure B<cpufreqd> (L<http://cpufreqd.sourceforge.net/>) or a
-similar tool is installed.
+similar tool is installed and an "cpu governor" (that's kernel module) is
+loaded.
=head2 mysql
=head1 RRD FILES
-The RRD files are created automatically with the following RRAs:
-
- RRA:AVERAGE:0.2:6:1500
- RRA:AVERAGE:0.1:180:1680
- RRA:AVERAGE:0.1:2160:1520
- RRA:MIN:0.2:6:1500
- RRA:MIN:0.1:180:1680
- RRA:MIN:0.1:2160:1520
- RRA:MAX:0.2:6:1500
- RRA:MAX:0.1:180:1680
- RRA:MAX:0.1:2160:1520
-
-Since collectd uses a 10 second I<step> the RRAs contain the following
-timespans:
-
- Resolution | Data points | Timespan
- -----------+-------------+----------
- 60 seconds | 1500 | 25 hours
- 30 minutes | 1680 | 35 days
- 6 hours | 1520 | 380 days
+The RRD files are created automatically. The size of the RRAs depend on the
+compile time settings of I<step> and I<width>. With the default values (I<step>
+= B<10>, I<width> = B<1200>) the following RRAs are created:
+
+ RRA:AVERAGE:0.1:1:8640
+ RRA:AVERAGE:0.1:50:1210
+ RRA:AVERAGE:0.1:223:1202
+ RRA:AVERAGE:0.1:2635:1201
+ RRA:MIN:0.1:1:8640
+ RRA:MIN:0.1:50:1210
+ RRA:MIN:0.1:223:1202
+ RRA:MIN:0.1:2635:1201
+ RRA:MAX:0.1:1:8640
+ RRA:MAX:0.1:50:1210
+ RRA:MAX:0.1:223:1202
+ RRA:MAX:0.1:2635:1201
+
+By default collectd uses a 10 second I<step>. Thus the RRAs contain the
+following timespans. If you've changed the I<step> at compile time you will
+have calculate resolution and timespan yourself.
+
+ PDP per CDP | Resolution | Data points | Timespan
+ ------------+--------------+-------------+---------
+ 1 | 10.0 seconds ! 8640 ! 1 day
+ 50 | 8.3 minutes | 1210 | 1 week
+ 223 | 37.2 minutes | 1202 | 1 month
+ 2635 | 7.3 hours | 1201 | 1 year
The DS'es depend on the module creating the RRD files:
projects / collectd.git / blobdiff