Since I migrated vCenter to 5.1, some vms are vMotioned to differents hosts every 5-10 min

[pbuch]

Hello !

I have a farm with two clusters (Clust A: 3 hosts, Clust B: 4 hosts). Yesterday, I migrated vCenter 5.0 to vCenter 5.1 and I had to reconnect all my hosts.

hosts are running ESXi 5.0u1, with all last patches

Since I migrated, 5-6 vms (always the same) from Clust A are vMotionned from hosts to hosts (they aren't all in the same host and they aren't moved into the same host), when it's successfully done, 5 to 10 min later they are vMotionned again and again... I read on the vm's event that DRS launched these operation

I post my problem to ServerFault and one guy told be to set the DRS' Migration threshold to a lower level (it used to be set at "Aggressive") so it stopped...

However, I still want to know why it does that ? I want to keep the threshold in Aggressive mode.

Clust B is running normally so... I'm quite scared...

Does one of you have an idea why?

Thank you very much for your help

Philippe

[ETastic]

If you've upgraded vcenter to 5.1, then why not upgrade the hosts, not all at the same time but a couple to see if you continue to have the same issue.

Also,

If you create a cluster with a default manual or partially automated mode, vCenter Server displays migration recommendations on the DRS Recommendations page. What does vcenter report here if anything?

[pbuch]

Thank you for your answer!

I migrated one host of three and it seems to work better, I progressively set the threshold more agressive and the behavior didn't appear again...

Thank you for your help

Phil.