Converting a server with ISCSI SAN mappings

[jasonvines]

I am looking to convert a physical server to virtual that has about 3.5 TB of data on an ISCSI SAN. My plan is to only convert the c drive and then map the existing LUNs used on the SAN using RDM. The problem I am running into during testing is that mapping an RDM for a virtual machine to a LUN that has been in use by a windows server. It prompts me to format the drive after it shows up. Will this work when I am connecting back through RDM with the original server that had the exclusive lock on the LUN? We are dealing with a very critical server and don't want to go through a test with it.

Thanks for any help.

Jason

[AndreTheGiant]

Are you using software initiator in your server?

If yes, you can still mantain the same configuration.

Andre

[jasonvines]

Yes I am using software initiator.

Thanks Andre!

[AndreTheGiant]

In this case convert only the system disk, and recreate your network configuration to use again the iSCSI initiator.

Andre

[jasonvines]

The OS ISCSI initiator or through vSphere? I would think it would be better to use it through my existing vSphere ISCSI software initiators on dedicated nics.

[AndreTheGiant]

I mean the OS guest initiator.

To use the vSphere initiator, you have to remap your LUN to the hosts, then attach the LUN as a RDM disk to the VM.

Andre

[jasonvines]

Do you think one provides better performance or less overhead over the other?

[AndreTheGiant]

RDM does not really mean more performance. See:

It depends by your, if you prefer have a VMs composed by vmdk (and also RDM has a vmdk), for example for backup reason, then use virtual RDM.

If you prefer keep the existing configuration, use guest initiator.

Andre