I work for a consulting / hosting firm in Topeka, and I have a server that is periodically crashing. The last couple of times, it appears to have been due to the server running out of memory. It is a virtual server (on VMware ESX), so I increased the RAM from 2GB to 4GB and the virtual CPUs from 1x single-core to 2x quad-cores. However, it may be a week or more before I can tell if this has resolved the issue.
What I am looking for is advice on how to track down the cause definitively, and prevent it from occurring again. (My client is complaining about the downtime.) When this occurred last time (~ a week ago), I installed sysstat to try and track the performance, but when I went to look at today's report, I got a message saying: "Invalid system activity file". Viewing yesterday's report works just fine, so I'm thinking that the hard-reset I performed this morning F'd up the report.
We would be willing to pay the right person for their expertise, and I hope to learn something in the process. I'm fairly knowledgeable, but I think I may be in over my head on this one.
The OS is CentOS 6.3, and it is dedicated to a single website running the Magento e-commerce software, which relies heavily on MySQL. Any advice or assistance would be appreciated.
Thanks in advance, ~ j.