[Xymon] Monitoring iostat performance

[Lists]

Recently, we had a publicly visible outtage as a result of one of our 
load balancers exceeding the IOPS capability of its system drives. We'd 
like to extend xymon (currently installed on CentOS6 /32 with defaults) 
so that it can monitor IOPS for all servers.

Specifically, we'd like to see wrqm/s and probably %util. What's the 
most straightforward way to accomplish this? The other alternative is to 
create some form of internal script, which is doable but not preferable 
if there's an off-the-shelf tool available.

-Ben