Recommended Windows Hotfix for Database Availability Groups running Windows Server 2008 R2

If you are using DAG configuration on your Windows Server 2008 R2 Servers consider applying the following hotfixes.

http://support.microsoft.com/kb/2549472 - Cluster node cannot rejoin the cluster after the node is restarted or removed from the cluster in Windows Server 2008 R2

http://support.microsoft.com/kb/2549448 - Cluster service still uses the default time-out value after you configure the regroup time-out setting in Windows Server 2008 R2

http://support.microsoft.com/kb/2552040 - A Windows Server 2008 R2 failover cluster loses quorum when an asymmetric communication fail

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