Two standalone ESX servers sharing one VMFS datastore

[TGoy]

We have two standalone ESX 3.01 servers (no VC, vMotion etc. available) and an attached iSCSI storage.

May both servers connect to the same vmfs3 datastore at the same time or will this call for trouble?

The idea is to manually stop VMs on one server and then start it on the other.

[Gabrie1 · Accepted solution]

Hi

Yes they may use the same VMFS3 datastore. You will have no problems with your vmdks, so your data is safe.

Only minor issue that might occure is that both ESX hosts try to manage the same VM (vmx-file). So you might have to unregister a VM on one host and reregister it on the second host. But this is very simple to do. Don't know what would happen if they both manage the same VM, if you still can start it on one host.

Gabrie

[mcwill]

In one word ... Yes.

Attach the iscsi LUN to the first ESX server and create your vmfs datastore.

Then on the second ESX server attach it to the same iscsi server and perform a storage rescan, this will then make the datastore visible on the second ESX server.

[BUGCHK]

an attached iSCSI storage.

This will call for trouble when the storage does not (properly) implement SCSI reserve/release requests from VMware ESX which is used to maintain VMFS volume meta-data integrity.

[arraya-halim]

If your iSCSI storage is an array listed on VMware's Storage HCL, you should be fine. Anything on the HCL should implement these SCSI requests properly.

[mikemohr]

Make sure the LUN ID is the same on both hosts. I'm not that familiar with iSCSI, so I'm not sure if you have a choice in the matter... but if they aren't when you rescan and try to add it it will just try to format the vmfs instead of just adding it as shared.