My ESXi-machine has been running for a long time, but I never took the effort to get some form of hardware-monitoring working. After the network at the datacenter went dark for a while, I thought that my machine had physically crashed. Luckily, the machine was still up-and-running, but it did scare me. Therefore, I decided to tinker around with some form of monitoring, and settled on Nagios (which I already had set up), and an addon script called ‘check_esx_wbem.py‘.
Firstly, I needed to enable CIM on my ESXi box. After searching around the advanced settings for a while, I found the following three options, and changed the first two from a ‘0’ to a ‘1’:
After that, I logged into the Tech Support Mode, I started the CIM-daemon:
Lastly, I went into the VI Client and executed a ‘Reset Sensors’ on the ‘Health Status’ page of the configuration. Afterwards, the ‘Health Status’ showed me the hardware-status of the machine:
With the ESXi configuration done, all I had to do was to configure Nagios, which was simple enough. I used an article on NagiosExchange. Thanks to Michiel Dijcks for helping me out with the Nagios part.
For an example how this would look in Nagios, please go here.