Forcing the clearing of persistent reservations on a disk formerly used by the cluster

 

It happens most of the time that while Cluster Failover occurs or due to some issue one of the disk or more went off line and on trying to being the resource online we get error as below.

Error:

The Cluster service failed to bring clustered service or application ‘SQL Server’ completely online or offline. One or more resources may be in a failed state. This may impact the availability of the clustered service or application.

Cluster resource ‘Disk E:’ in clustered service or application ‘SQL Server’ failed.

Reason:

If disk failover occurs but the server that takes ownership of a disk cannot read it, the cluster cannot maintain availability of the disk. If information written to the disk is changed during the process of failover, it could cause issues for users or software that requires this information. In either case, if the affected disk is a disk witness (a disk that stores cluster configuration data and participates in quorum), such issues could cause the cluster to lose quorum and shut down.

Resolution:

Open the Disk Management under storage of Computer management .Get the disk number which failed.

Open Command Prompt with “Run as Administrator”

Run the command in command prompt

Cluster node Server name /clearpr:DiskNo(ex:5)

Ex: cluster node cpnftsdtdb1 /clearpr:5

Once clearing of persistent reservations on the disk is done. Try to bring the resource online.

Failover Cluster from Command Prompt

We all have learnt how windows cluster work and how SQL Server works with Windows Cluster.

As a database administrator i deal everyday with clusters and clusting issues.

Here we will see how to check Cluster,Cluster Resources,Nodes etc from Command Prompt and also how to failover to the available nodes.

It will help you check cluster resources when the Cluster GUI is not able to provide proper information in case Disk Hangs, failover is taking longer then expected etc.