vcenter: host resource usage shows 0MHz, 0MB
i noticed this issue nearly a month ago. after a host would be running for a couple of days and joined to vcenter the resources pane on the summary tab would look “blank” (as in cpu usage: 0mhz, memory usage: 0mb). the first time i saw it i rebooted the host and the issue went away.
later on, i saw the issue return to the same host and then also spotted it on other hosts. it was obvious this was a bug at the time (since there were powered on vms on these hosts). however, i wasn’t immediately that concerned with it. a reboot would temporarily resolve it.
this bug started to annoy me when i actually needed to vmotion vms around as i was basically driving blind without resource stats. still, i didn’t experience real concern until i noticed that DRS was believing these false stats and completely evacuating hosts that were affected by the bug. i couldn’t have perfectly healthy hosts running zero vms. at this point i decided to look into it and found it listed in a vmware kb article. the issue is resolved by upgrading to vcenter 5.1u1a or later.