Installing the Drupal Munin server
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1 Install Munin and the module
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The module is designed for Munin 1.4.4 and above. Use the normal Munin deployment for your platform.

It is known to work, albeit with some warnings and limitations, on Munin 1.2.6 (Ubuntu 9.04/Karmic).

On Debian/Ubuntu, you will find configuration in /etc/munin 

Install the module on Drupal, and enable the submodules you wish to use. 
Default submodules are provided to monitor Drupal core (content, users), and the 
PHP APC opcode cache. 


2 Declare the plugin to Munin
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A sample plugin is provided with the module as plugins/munin-drupal_, which you
can either use as such or customize as needed. The sample plugin uses CURL to
contact your Drupal site to obtain its data. 

You will usually copy it to a directory in your $PATH, like /usr/local/bin, or 
createa link to it from that directory, like:

  ln -s <drupal>/sites/all/modules/munin_api/plugins/munin-drupal_ /usr/local/bin/munin-drupal_
 

3 Configure the plugin in Munin
-------------------------------

Edit the /etc/munin/plugin-conf/munin-node file to declare the plugin

Add a section for your plugin. If you are using the sample plugin provided with
the module, it needs to know the hostname of the site to monitor, which is not 
always the same site as your Munin instance.

  [drupal_*]
  env.HOST mysitename.mydomain.tld


4 Check
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Once declaration and configuration are done, you need to force munin-node to
update its configuration. On Ubuntu 10.10, for instance, use:

  sudo service munin-node reload

Assuming you enabled Drupal core and APC monitoring. You can then check the module configuration:

  munin-run drupal_core config
  munin-run drupal_apc config  
  
Then check their data:
 
  munin-run drupal_core
  munin-run drupal_apc  
  
5 Modify configuration
----------------------

Any time you enable/disable a Munin submodule or modify its settings, you will
need to force a munin-node configuration reload so that the server knows what to 
plot.