I have a question that I got an interesting and helpful answer for on the IRC channel today, but thought I'd open it up to a larger group as well.
My problem is hopefully a very common problem. I'm using Ganglia for trend graphing. We are using Ganglia 3.0.7 for convenience since RPMS are available for CentOS 5.4 through EPEL. Everything generally works great, but Ganglia doesn't appear to gather Disk I/O stats ( writes/sec, reads/sec, etc ) as a metric. Some quick looking on the web seemed to confirm that ganglia doesn't capture disk I/O stats by default, but talk about how it's generally pretty easy to capture using gmetric.
I guess my question would be is there a common way of doing this? What do you use? Do you find Disk I/O to be a useful/necessary metric?
Any thoughts would be much appreciated.