Set up a Collectd client

09-04-2013 | Remy van Elst

Table of Contents

This tutorial shows you how to set up a collectd client for use with a collectd server. What is collectd? collectd gathers statistics about the system it is running on and stores this information. Those statistics can then be used to find current performance bottlenecks (i.e. performance analysis) and predict future system load (i.e. capacity planning). Or if you just want pretty graphs of your private server and are fed up with some homegrown solution you're at the right place, too ;).

You need a collectd server set up to fully use this tutorial, but I also have written a tutorial to do that.

The collectd server tutorial can be found here and a Ansible playbook to set this all up can be found here

The collectd client is much easier to set up than the server with web frontend. It only requires installation and configuring the client.

Installing Collectd

First install all the required packages:

sudo apt-get install collectd 

Configuring Collectd to talk to our server

Open your favorite editor and edit the /etc/collectd/collectd.conf file. Read it, then remove it all and make sure it looks like the below config file:

## /etc/collectd/collectd.conf generated for by Ansible
## Config Type: CollectD Client

Hostname $HOSTNAME
FQDNLookup false
Interval 30
ReadThreads 1
LoadPlugin syslog
<Plugin syslog>
        LogLevel info

LoadPlugin cpu
LoadPlugin df
LoadPlugin disk
LoadPlugin entropy
LoadPlugin interface
LoadPlugin irq
LoadPlugin load
LoadPlugin memory
LoadPlugin processes
LoadPlugin rrdtool
LoadPlugin swap
LoadPlugin users
LoadPlugin network

## Extra Plugins
LoadPlugin nginx
LoadPlugin iptables
LoadPlugin uptime
LoadPlugin dns
LoadPlugin ping

## CollectD Servers
<Plugin "network">
        Server "$COLLECTD SERVER IP" "25826"
        Server "$COLLECTD SERVER IP" "25826"
        SecurityLevel None

<Plugin rrdtool>
        DataDir "/var/lib/collectd/rrd"

Include "/etc/collectd/filters.conf"
Include "/etc/collectd/plugins.conf"
Include "/etc/collectd/thresholds.conf"

The configuration file is relatively simple. Make sure to replace $VARIABLE$ by the correct on for your server. You load plugins via "LoadPlugin $name". The network part is important, this configures our client to send its data to our server. Replace $COLLECT SERVER IP with your collectd server IP.

Make sure the file has a blank newline at the end. If it has not, collectd will fail to start/run correctly.

Configure collectd plugins

Now create the following file: /etc/collectd/plugins.conf, it doesn't exist by default. This will house the plugin config. Add the following content to it, but make sure it matches your LoadPlugin settings above. If you don't have the ping plugin, you also don't need the config for it.

## /etc/collectd/plugins.conf 

## Static Plugins (every host has them)
<Plugin swap>
       ReportByDevice false

## Dynamic Plugins 
<Plugin nginx>
       URL ""

<Plugin ntpd>
       Host "localhost"
       Port 123
       ReverseLookups false

<Plugin ping>
       Host ""

<Plugin sensors>
       SensorConfigFile "/etc/sensors3.conf"
       Sensor "it8712-isa-0290/temperature-temp1"
       Sensor "it8712-isa-0290/fanspeed-fan3"
       Sensor "it8712-isa-0290/voltage-in8"
       IgnoreSelected false

<Plugin write_graphite>
               Host "$GRAPHITE_HOST$"
               Port "2003"
               Prefix "collectd"
               Postfix "collectd"
               StoreRates false
               AlwaysAppendDS false
               EscapeCharacter "_"

Collectd server is now set up in "client" mode. To test it we restart the service:

/etc/init.d/collectd restart

And then check the /var/lib/collectd/rrd/ folder and you should see some files and folders (rrd libraries). If not then your collectd is setup wrong, see syslog for more info.

We also should see these files on the collectd server, in the /var/lib/collectd/rrd folder. If you see them there, you have done it correctly.

Remember to add the IP to the collectd server firewall.

Now you have a fully working collectd client set up. The collectd server tutorial can be found here, and a Ansible playbook to set this up can be found here

Tags: collectd, monitoring, munin, rrd, rrdtool, statistics,