SQL 2008R2 instance taking long time to fail-over after SQL 2012 Upgrade.

Hi,

I've a 2-Node cluster of Windows 2008 R2 Ent where we are having multiple SQL instances running. I've upgraded an instance to SQL Server 2012 from SQL Server 2008 R2. Ever since failover of other instances running SQL Server 2008R2 is taking long time to bring SQL Services online in the cluster. And it fails after 3 minutes (Pending Timeout default setting).

I've verified the SQL instance during the state change (from offline to online), I found out that SQL Server is available that time just cluster is not able to change the state and it time out. There is no information in cluster logs at that point of time.

Have someone faced the similar issue and any pointer to check it further? Can it be related to cluster resource DLLs which were updated while upgrading to SQL 2012?

Looking forward to your cooperation.

Regards,

Divesh Mathur