Thursday, July 17, 2014

Mixed SIOC environment causes DRS migrations to fail

Issue : The VM migration failed continuously for a vm causing it to freeze and power off.

Why ?: Apparently few of the hosts of the cluster didnt have the enterprise or required license to enable SIOC and thus the DRS was trying just trying to migrate it to the host which unfortunately didnt have the SIOC enabled because it didnt have the enterprise license.
So if the target host doesnt support SIOC, source host from which the VM is moving has SIOC then you will face this problem. I am yet to see such more incidents to conclude that DRS is not  SIOC aware. May be some giants should shed some light on it. Obviously they werent using SIOC on all of the datastores but you see the conflict of interest when some hosts are relying on SIOC to make decision on the same datastores on which the SIOC isnt enabled/used for other hosts of the same cluster.

Resolution: upgrade the remaining few hosts with the enterprise license and enable SIOC on them too.