DSSv6 Failover + MPIO + Windows 2008 Cluster Issues

[pfeifferl]

Hello,

I encountered some troubles with DSS v6 iSCSI auto failover in combination with Windows 2008 R2 failover cluster when using MPIO.

When doing a failover/failback on DSS one of our two Windows cluster nodes reboots with a BSOD. If we use only one iSCSI connection without MPIO there is everything running smoothly (with small warnings/errors on cluster disks).

Some comments from open-e? Do you have tested this combination (DSS failover + Windows R2 cluster + MPIO)?

DSS failover + MPIO is ok, DSS failover + Windows R2 cluster is ok, but all three there are troubles ...!?

[pfeifferl]

Seems to be a problem with Intel I/OAT ... I disabled I/OAT in BIOS and this issues was gone.

But: There is still a problem with the Hyper-V VMs - sometimes while DSS failover the VMs running on cluster are crashing ...

It seems that the DSS failover is not fully transparent to the iSCSI initiator and the VMs ... I lose only 1 ping on iSCSI LAN connection while failover, but the cluster disks are going offline and online again and that's not good for the running VMs ...

Is open-e working on this issues?

[pfeifferl]

not a solution, but a work-around: I put all Hyper-V virtual machines to save state, then DSS failover (e.g. for updates ...), then failback and starting the VMs again ...

[cphastings]

What good is clustering if you have to do that? =)

[pfeifferl]

Yes, I hope open-e will fix that issues ASAP, but in the meantime this is the only possibility. It's not without downtime, but with only a very short outage (going to save state, failover, recover from save state = only a few seconds ...). Without DSS failover the maintenance windows would be much longer ...

[enealDC]

There are some solutions that you can try:

Look here:

http://sustainablesharepoint.com/

and here:

http://www.microsoft.com/communities...r=US&sloc=&p=1

I'm still testing on Win 2008 with MPIO and failover too - so I of course am going to test as well.

[enealDC]

Actually, let's tighten that first link up a bit http://sustainablesharepoint.wordpre...-v-with-iscsi/

[dweberwr]

Wow, great information! Planning on putting in a dss box via iscsi this summer for several hyper-v servers, this is the stuff I want to know about! HA and failover are not on the radar for us for this implementation but it is something I want to strive for.