SRDF/Metro with vWitness

Hi,

Apologies if my question is submitted in the wrong thread. I would like some input to migrate or rather change the underlying replication of Virtual Volumes from VPLEX to SRDF/Metro with a vWitness on a remote site. All clusters are MSSQL and consists of two nodes across two sites (node per site). On each VMAX there's a VPLEX SG with all the tdevs presented through to the two VPLEXs to form the Virtual Volume then presented through to the virtual SQL servers(s) as RDMs in physical mode. The same two VMAX100k underpinning the above will be used for SRDF/metro with a vWitness. The datastores for vmdks presented to the same VMware based MSSQL clusters e.g. the C: drives etc. are in a different Storage Group.

Here is my thoughts so far.

1. Create a SRDF/Metro group with the label as the cluster name (Type witness and not Dynamic) with limbo mode set at 1.

2. Create a child SG per VMAX in the Parent SG where the luns for datastores are in.

3. Dual present the tdev in the VPLEX SG also to the new child SG in the "other" Parent SG

4. Create a pair of SRDF/Metro devices specifying the correct parameters and new child SG on the local and remote site. This will change the personality of the tdev dual-presented in two SGs from tdev to rdf+tdev.

5. Do not present the rdf+tdev devices to the cluster from the new child SG as RDMs yet.

6. Wait for sync to complete.

7. Power off both nodes of the cluster and remove the RDMs (only remove from vm!), also taking note which disk is what SCSI id e.g. 1:0 etc. (We start at SCSI 1:x plus for RDMs in our environment)

8. Add same RDMs from the child SG to the nodes with the same SCSI id.

9. Power on nodes in the cluster and test.

I realize there is some cleanup tasks etc. not included but would like to find out if my approach is correct of if I'm potentially overseeing a major flaw in my high-level plan.

(All kit involved are one the correct code/version ex. MSSQL versions and OS)

Thanks you.