srm, snapmirror and RDMs

[ejacobs]

We have a rather large vm that has a 500G RDM attached. Client is convinced that netapp snapmirror based replication is the way to go (he thinks that replication would be less taxing on the vm than Vsphere replication). My dilemma is that the regular disk is on one volume and the rdm is on another. I suppose I could snapmirror both volumes but would recovery pick that up? Or should I try to move regular disk to same volume as rdm (there is room)?

[GreatWhiteTec]

Keep them separate. I would recommend having the OS volume(datastore) by itself with no other VMs in it. Have a Vol per LUN (RDM). When you add the RDM to the VM it will create pointers to the LUNs. As long as the Volumes containing the LUNs (RDMs) have a snapmirror relationship, SRM will recognize that.

The reason for having the OS in its own datastore (vol) is so that you can have the VM in its own protection group. Say this VM is an Exchange Server and you only want to failover Exchange, this is the way to go.

[ejacobs]

OK, if I understand what you're saying, I can snapmirrot the volume with the OS disk and the volume with the RDM, set up my protection and recovery and when it fails over, the new vm at the failover site will have both disks

[GreatWhiteTec]

Yes. When you create the RDMs, just keep the pointer files in the OS Volume. If you have issues, let me know. I have done quite a few of these. BTW snapmirror is better for replication in my opinion. It keeps the workload out of vsphere.