In a failover cluster, virtual machines can use Cluster Shared Volumes that are on the same LUN (disk), while still being able to fail over (or move from node to node) independently of one another. Virtual machines can use a Cluster Shared Volume only when communication between the cluster nodes and the volume is functioning correctly, including network connectivity, access, drivers, and other factors.
Message: Cluster Disk '%1' has been removed and placed back in the 'Available Storage' cluster group. During this process an attempt to restore the original drive letter(s) has taken longer than expected, possibly due to those drive letters being already in use.
CSV - Review drive letter assignments
When a disk is removed from Cluster Shared Volumes (CSV), the system attempts to re-assign the disk the same drive letter that it previously had (based on information that was stored when the disk was added to CSV). If that drive letter is now assigned to another disk in use on any node of the cluster, it is no longer available. You can choose one of the following responses:
Find the disk that is currently using the drive letter and manually change it to another drive letter. Then assign the original drive letter back to the disk that was removed from CSV.
Assign a new drive letter to the disk that was removed from CSV.
Use a GUID instead of a drive letter for the disk that was removed from CSV.
If you do not currently have Event Viewer open, see "To open Event Viewer and view events related to failover clustering."
To perform the following procedure, you must be a member of the local Administrators group on each clustered server, and the account you use must be a domain account, or you must have been delegated the equivalent authority.
To open Event Viewer and view events related to failover clustering:
If Server Manager is not already open, click Start, click Administrative Tools, and then click Server Manager. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Continue.
In the console tree, expand Diagnostics, expand Event Viewer, expand Windows Logs, and then click System.
To filter the events so that only events with a Source of FailoverClustering are shown, in the Actions pane, click Filter Current Log. On the Filter tab, in the Event sources box, select FailoverClustering. Select other options as appropriate, and then click OK.
To sort the displayed events by date and time, in the center pane, click the Date and Time column heading.
Confirm that the Cluster Shared Volume can come online. If there have been recent problems with writing to the volume, it can be appropriate to monitor event logs and monitor the function of the corresponding clustered virtual machine, to confirm that the problems have been resolved.
To perform the following procedures, you must be a member of the local Administrators group on each clustered server, and the account you use must be a domain account, or you must have been delegated the equivalent authority.
Confirming that a Cluster Shared Volume can come online
To confirm that a Cluster Shared Volume can come online:
To open the failover cluster snap-in, click Start, click Administrative Tools, and then click Failover Cluster Manager. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Yes.
In the Failover Cluster Manager snap-in, if the cluster you want to manage is not displayed, in the console tree, right-click Failover Cluster Manager, click Manage a Cluster, and then select or specify the cluster that you want.
If the console tree is collapsed, expand the tree under the cluster you want to manage, and then click Cluster Shared Volumes.
In the center pane, expand the listing for the volume that you are verifying. View the status of the volume.
If a volume is offline, to bring it online, right-click the volume and then click Bring this resource online.
Using a Windows PowerShell command to check the status of a resource in a failover cluster
To use a Windows PowerShell command to check the status of a resource in a failover cluster:
On a node in the cluster, click Start, point to Administrative Tools, and then click Windows PowerShell Modules. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Yes.
If you run the preceding command without specifying a resource name, status is displayed for all Cluster Shared Volumes in the cluster.