SAN management

LUN expansion with Microsoft cluster server

LUN expansion with Microsoft cluster server

By  Christopher Poelker

We are planning to upgrade our EMC storage box by adding additional DAE2 enclosure. Currently, there are four two node cluster are accessing the box. We are planning to increase the LUN size of each cluster. After changing the LUN size, will the cluster will work? We have Windows 2003 cluster servers.
Microsoft cluster resources require basic disks, as dynamic disks traditionally are not supported within the cluster. This is because dynamic disk resource info is kept in the local registry, and the other node would have issues during a failover. If you happen to use Veritas Foundation Suite 4.2 or above on top of the Microsoft cluster, then LUN expansion is a simple matter of right clicking on the disk resource and expanding the disk to whatever size the array is presenting.

If you are using standard Windows 2003, then you can use the "DiskPart.exe" utility from the Microsoft resource kit.

Use the "rescan" command at a command prompt with diskpart.exe to allow the OS to see the additional free space for the drive. Then use the "extend size = xxxx" command to extend the disk.

18 Jan 2006