Riak exposes monitoring data via JMX. To enable JMX monitoring, edit the app.config and set the enabled property of the riak_jmx section to true, as follows. The TCP port that the JMX provider listens on is also configurable in this section (the default JMX port is 41110).

    {riak_jmx, [
        {enabled, true},
        {port, 41110}
      ]}

To view JMX data if you have the Sun JDK installed, launch JConsole as follows:

   % jconsole <hostname_to_monitor>:<jmx_port> 

Once connected, click on the 'MBeans' tab, expand the 'com.basho.riak' tree view, and select 'Attributes'. The attributes listed below will be displayed.

Riak JMX has been tested with the Sun JRE 1.6.0_12 and 1.6.0_20. Some older/non-Sun JREs do not work (e.g. the default java-gcj JRE installed on debian lenny). If you have problems with JMX or see the message below, please try upgrading to the Sun JRE:

   =INFO REPORT==== 9-Jun-2010::08:14:57 ===
   JMX server monitor <pid> exited with code <non-zero>.

Exported JMX Attributes