Maintenance mode no longer migrating machines

[WinkIT]

This just started happening this weekend....when I try to put any of my hosts into maintenance mode, the VMs aren't being automatically moved off of that host. Under events, it just says "Unable to automatically migrate GUEST from HOST" DRS is set to Full Auto, and moving all of these around shouldn't violate any HA constraints. I can manually VMotion the machines off and throw the host into maintenance mode, but that obviously takes forever. The ESX hosts are running 3.5 U2, completely up to date (except for the kernel update that came out 9/18) VC is also completely up to date. Both the VC server and all of the ESX hosts have been rebooted and the problem is still happening.

Anyone have any ideas?

[Rubeck · Accepted solution]

Hi

Have you tried to switch off HA before entering maint. mode?

Just to see if this is what causing it...

And you have seen the release notes for U2, right?

Known issue:

Copy /paste from

"Virtual Machine Migrations Are Not Recommended When the ESX Server Host Is Entering the Maintenance or Standby Mode

No virtual machine migrations will be recommended (or performed, in fully automated mode) off of a host entering maintenance or standby mode, if the VMware HA failover level would be violated after the host enters the requested mode. This restriction applies whether strict HA admission control is enabled or not. "

/Rubeck

[WinkIT]

Yeah, I read that last night, but I can't imagine how I'd be violating my HA constraints by throwing this host into maintenance mode. I'm disabling HA right now, and we'll see what happens.

[WinkIT]

So disabling HA did the trick, but I don't understand why...my HA failover level wouldn't have been violated with only 1 host in maintenance mode. Oh well, I'll just have to live with it for the time being.