I wrote this post up, but it ended up being pretty lengthy. You can find the full text over here -> Monitoring Apache and MySQL with RRDTool
Here’s the intro text:
I’ve been having some problems with my webhost falling over, so I decided to implement some pretty graphs to help me get a better grasp on what was going on. The issue appeared to be some combination of apache, mysql, and ram usage that would occasionally drain the machine of memory. This is also running on John Companies’ virtual colo service, so I’m not sure if that’s a factor or not, but hopefully I can find that out. They had graciously bumped up my memory limits multiple times, so I was somewhat confident the error was on my side. I was inspired after switching my utility box at home to Gentoo and needing to setup my snmp monitoring tools again. Wanting to migrate to rrdtool, I came across the Advanced SNMP Monitoring with RRDTool and saw that it was quite easy to incorporate other system properties in monitoring data, such as process and disk usage. I’m also going to use this article about Using SNMP and RRDTool on FreeBSD as I don’t want to use MRTG (despite the catchy little jingle I dreamed up about 6 years back to the tune of ‘Getcho Freak On’) to do the polling.