We use PRTG to monitor our ESX 4.1 Environment, which includes VM Lab Manager. We use our VMs mostly for performance testing and as such run pretty high on the CPU and Memory side. As a result we seem to get a lot of downs and immedeate ups (within the same minute often) related to ESX Server health:
ESX Server Health (VMware Host Server (SOAP))
On the other hand, Vcenter and Lab Manager seldom register a error (unless the machine losses communication with them), nor are users impacted during these PRTG alarms. Please also note, the ping sensor never reports the ESX server as down. So, it responds to ping, and the VmWare Infrastructure, yet fails the ESX Server Health check long enough to trigger an alarm.
My questions are as follows:
1) Could someone explain briefly the basic functions of the ESX Server Health Sensor?
2) How do SOAP based sensors compare to ICMP? As in why are pings still up and yet these sensor calls go up/down?
3) What are the "best practices" settings for this sensor? Both for monitoring and then for the threshold to trigger an alarm?