[Nagiosplug-help] Nagios Plugin for tomcat

[Olivier 'Babar' Raginel]

On Wed, Mar 10, 2010 at 04:46:28PM +0530, Kaushal Shriyan wrote:
> is there a Nagios Plugin to measure XMS (minimum heap size) and XMX
> (maximum heap size) which is a parameter to set for CATALINA_OPTS for
> tomcat application server?

I think I've already mentionned this in a thread on this list, anyway, 
there are 2 ways to monitor the heap size of a JVM.
Monitoring XMS and XMX as you say is totally useless. You start the 
server, you should be able to put these values somewhere so you can 
check them. But what you're interested in is the memory usage of the 
application.

And in Java, you have 2 ways to do so. One is using SNMP, which gives 
you some access to a limited number of variables, and the other one is 
through JMX, which is expandable.
I've done both, they have their pros and cons, SNMP major drawback is 
that it is limited, so anything not displayed through the MIB will not 
be accessible, and it also does not work well if you already use JMX.
The main problem with JMX is that all clients to poll some JMX are 
written in Java, so it is slow for a nagios plugin.

I'll see if I can release some of the N::P I wrote for that, but using 
SNMP should be pretty straight forward.

-- 
Babar.