Do NOT put the DSM/MPIO stuff on a VCB/VADP box. (When Upgrading to 9.0)

[JonInfrastructure]

Hi People.
I run the CMC on a windows box that is also used for backing up our DMZ ESX farm (Commvault VADP).

Where I went wrong was by blindly following what the CMC was telling me to do before the upgrade which was to install the DSM/MPIO provider and the VSS provider. The upgrade went well, apart from a couple of the LUN's disappearing and re-apparing as the VIP moved around, and then all hell broke loose.

My ESX Servers started dropping into the greyed out 'not responding' state in vCenter, although it appeared all the VM's they were running were still up. After 2 days of troubleshooting with the help of HP and VMware I was finally pointed to VMware KB 1030129 which states 'HP Lefthand DSMs for MPIO can cause locking and LUN accessibility issues on LeftHand arrays'. After I removed the DSM on the windows box which had the LUNs presented all was well.

My point to the whole story: Do NOT put the DSM/MPIO provider on a windows box that has ESX Luns presented to it, even though it appears to be a pre-requisite (if you have the CMC on that windows box)

Anyway I hope this might save somebody making the same mistake I did and tearing their hair out for a couple of days.

BTW: The ESX Boxes are running 4.0U2, I am trying to ask if 4.1 with VAAI will still have this issue.

Cheers to All.

[Fred Blum]

Hi Jon,

The Upgrade Now installer did not tell you to install the DSM MPIO and VSS providor. It told you that if you are using that software that it is a prerequisite to update that software FIRST before SECOND attempting an update of the SAN.

I had DSM MPIO installed with Windows Cluster Server 2008 R2 2 nodes and ran into this problem also. So did kghammond with Windows Cluster Server. It is not limited to ESX luns.

It is a painfull bug and in my case HP support did not know or acknowledged the cause.

[kghammond]

Does anyone know if there are compatibility issues using vRanger's iSCSI offload feature with the HP Lefthand MPIO DSM?

We previously ran the HP MPIO DSM 8.5 on our vRanger box using the iSCSI offload. All iSCSI offload LUN's were mounted read-only. Everything seemed to work fine. We only had one NIC though so we were not doing MPIO.

We have moved vRanger to a new box and loaded 9.0 DSM on it and this box has four nic's for iSCSI. We have been debating about using MPIO on all four nic's for each LUN. We have about 50 LUN's so this could be painful. Or we were also considering doing a poor man's load balancing and just logging on one NIC per LUN and let the backup system load balance the nic's. As of right now we are just doing over the LAN backups.

Any thoughts or suggestions?