Expand your SAN partition on your Windows 2000 or Windows Server 2003 Cluster Shared Disk


How can we expand a couple of volumes in our SAN infrastructure that are used for our Clustering solution?


I have Knowledge Base article 304736 – http://support.microsoft.com/default.aspx?scid=kb;en-us;304736.   How much downtime am I looking at?



Great question! I did this not that long ago… The dispart part is seconds. And I mean seconds. Lets break down the Q article steps (Microsoft steps in italics, my comments in bold):


First you have to prepare the SAN, which should not involve any downtime for the SAN or your cluster. This of course assumes that your SAN allows this action (contact the hardware vendor). Depending on the amount of space added this step could take from minutes to weeks.



Back up the shared disk (or disks) that that you want to extend.

Excellent idea. You just never know J


Power off all but one node in the cluster.

Yes, I mean completely power them off – nodes 2-8 (if you have that many).


Take the entire group that the physical disk resource is located in offline. Bring only the physical disk resource that is to be extended online. This process should close any open handles to the disk.

This is where the outage starts. Make sure you on the controlling node (the only booted on at this point) when you do this step.

NOTE: If you have any disk or Host Bus Adapter (HBA) utilities that access the disk, you may need to quit them or stop the services so that they will release any handles to the disk.

Good advice.


Add the additional physical drives and extend the additional disk or disks as free space by using the instructions that are included with the hardware vendor documentation.

I had not had to do anything with this step, but you might. Again, check with your hardware vendor before proceeding.


Click All Programs, point to Administrative Tools, click Computer Management, and then start the Disk Management console. Verify that the new free space is added to the end of the proper drive. Right-click the existing partition, and then click Properties. On the General tab, type a unique name for the partition. This name will be used to identify the partition you want to extend in Diskpart.exe. Quit Computer Management.

You might have to Rescan to see the new space. You may already have a name for the partition, if so you don’t have to give it a new name (as long as the first name is unique).

NOTE If you encounter any problems with the preceding two steps while you are extending the drive, contact your hardware vendor for assistance.


At a command prompt, type DISKPART, and then press ENTER to start Diskpart.exe.


Type LIST VOLUME, and then press ENTER to display the existing volumes on the computer.


Type SELECT VOLUME volume number, and then press ENTER, where volume number is the number of the volume that you want to extend. Note that the volume will have the unique name that you created in step 5, and will have been listed in the output of the command you ran in step 7.

Aren’t you glad you name the partitions already?


Type EXTEND, and then press ENTER to extend the partition into all of the available disk space to the end of the drive.

Dang, that is easy! Yes, it only takes a few seconds to extend. Can I bill the customer for a 3 minute job? Of course I can and will J


Type EXIT, and then press ENTER.


Now that the volume has been extended, you can bring the entire group that contains the physical disk resource online, and then power up all of the other nodes in the cluster.

Don’t hold your breath, this step is simple.


Verify that the group can come online and failover to all other nodes in the cluster.

Tip – turn the rest of the nodes on before you try to move group to them J

As you can see, it’s really not that hard! The last time I did it on a two node cluster, the outage was under 20 seconds, though I still preformed it during a maintenance window 🙂 The whole process under 3 minutes with proper preparation.

3 thoughts on “Expand your SAN partition on your Windows 2000 or Windows Server 2003 Cluster Shared Disk

  1. Wonderful! This is simply amazing. I was able to extend a 1.5 TB drive in less than 1.5 secs. If you follow the instructions down to the wire then everything will work. Thanks for the wonderful instructions Rodney. Appreciate it.



  2. Very very useful…

    I’ve upgd our Veritas application Disk (clustered) with out any issue. We had a 50 GB SAN Disk and have upgd it to 150GB.

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