I recently had another one of my weird Snapdrive issues while trying to resize an iSCSI Lun on a 2003 server. The server is a VM that is using the Microsoft iSCSI initiator and Snapdrive to manage the Netapp provisioned Lun. Re-sizing a lun using Snapdrive is normally very simple but of course on this particular day it was not behaving for me.
Snapdrive appeared to be running ok and didn’t seem to have any issues at all that day. The problem came when I attempted to re size the lun, Snapdrive re-sizing process would fail halfway through. The failure to complete the re-sizing left me puzzled since all connections to the filer appeared to be fine. There was plenty of space left on the volume so it wasn’t a space issue.
Since we were dealing with Windows here we rebooted the server just in case it was pending a reboot or it just needed to “clear it’s head”. After the reboot I attempted to re-size the lun again and again it failed . The actual failure message was that it was unable to connect to the disk. Odd…It’s connected in Snapdrive , it just won’t resize.
The next thing I thought of was to force a disconnect on the iscsi lun, this way it would forces a disconnect on all connections. The downside to the disconnect was that the Lun would be lost and the SQL databases would need to be stopped. After getting approval to take the server down again, I then proceeded to force a disconnect of this lun. Once all connections were stopped and confirmed they were gone, I then reconnected the iSCSI Lun using Snapdrive.
After the re-connection was completed, I continued with trying to re-size the Lun. BAM! It worked. All it took was a force disconnect , reconnect, then I could re-size. To be honest , I wasn’t in the mood to go further digging into a root cause for the failure, especially since I got it working now. I suspect it had something to do with Snapdrive and the iscsi connection it was using since a brand new connection seemed to clear any issues that it had previously. So, if you run into something like this, it might be worth a force disconnect to solve your re-sizing problem.