I am using VMWare Site Recovery Manager (SRM) at two locations. One is my primary data center (PDC) and one is my disaster recover (DR) data center. I have two EqualLogic PS 4110 arrays at each location. The EqualLogic arrays have many volumes which replicate on a schedule to the DR site.
In all but one test, SRM failed during the reprotect step.
Error on reprotect:
Failed to reverse replication for device ‘iqn.2001-05.com.equall-ogic:0-af1ff6-xxxxxxxxx-xxxxxxxxx-xxxxxx-xxxx.1’.
I would also see problems with the array pair in the SRM Dashboard:
This all makes sense once you understand what went wrong.
Understand the limits of the Storage Replication Adapter (SRA)
The SRA acts as a middle man between SRM and the EqualLogic Array. It does not do a good job of producing an error a human can understand or even find. What you are left with is the vague errors you see in SRM which are not helpful. They key is in the message “Device ‘XXXX’ cannot be matched to a remote peer device.”
The SRA will only work with one storage pool. I had two storage pools at PDC and one at DR. It wasn’t the mismatch that mattered, it was the fact that I had two pools. I could have had two pools at both sites and received the same error.
How it fails
I created a volume on Pool B (The second pool) at PDC and replicated it to DR. When I clicked reprotect in SRM, the SRA tried to find the volume on Pool A. The volume didn’t exist, because it was in Pool B, and this SRM barfed the dreaded “Failed to reverse replication for device ‘iqn.2001-05.com.equall-ogic:0-af1ff6-xxxxxxxxx-xxxxxxxxx-xxxxxx-xxxx.1′” error.
You can however reprotect any VM on a volume from Pool A without error.
How to fix it
In my case the solution was simple. I merged the two pools. My next test of SRM worked. The other option is to only protect VMs in Pool A.
This is an annoying issue which I hope Dell fixes in future versions of the SRA. If I were to buy another array I would be unable to use SRM to protect my VMs because I would have multiple pools.
If you are considering buying a Dell EqualLogic array, consider this limitation carefully if you are going to use SRM. Your ability to grow over time will be limited by the SRAs inability to deal with multiple pools.
Decomplexification 