Manually moving SAN based VMs between ESX servers

[vmcms]

The best answer to this question is Vmotion but I'm running "Starter" 3.5 and don't have a Virtual Center Server. If I right click on a stopped VM I don't have a Migrate or move command. I'm assuming this is a limitation of my licensing.

On my Storevault SAN there is a LUN. The LUN is an iSCSI target for one of my ESX servers. I want to accomplish the following:

Move a VM from one ESX server to another

Recover SAN based VMs in the event that one ESX server fails.

I've been moving the LUN from one ESX server to another by changing the initiator to the desired ESX server. This makes the source ESX server unhappy and confused and eventually the VI client stops updating Storage objects.

I have very little experience with Linux, ESX, or SANs. I feel like I'm working on a Swiss watch with a hammer while wearing mittens. Is there a better way to do what I'm trying to do without implementing Vmotion?

Thanks!

[juchestyle]

Hey man,

So all your esx hosts can see the same storage right?

You should be able to right click on a vm and remove it, or unregister it from a host and then on the other host create a new vm but point to an existing vmdk. Not super clean but doable. Does this make sense?

Respectfully,

Matthew

Kaizen!

[vmcms]

Thanks Matthew,

Both ESX servers can see LUNs hosted on the same SAN but I don't think it's possible to "share" a LUN simultaneously between two initiators. Executing "Remove from inventory" for a source VM might provide a more orderly removal of the VM from the source ESX server.

It would be nice if there was a way to remove Storage without the contents being deleted. I suspect this is limited by design for product marketing purposes.

Thanks for your reply.

[christianZ]

Are you using the esx iscsi software initiator?

It should be possible to share one lun over 2 or more esx hosts - I think.

You shouldn't simply remove the lun access from the first esx host - it won't be happy. Just add access to this lun for your second esx host.

[juchestyle]

I agree, you should be able to share a lun with I think up to 32 ESX hosts, 16 if they have two hbas, not sure how it works out with iscsi. I have Mad skills with vmware, but my SAN skills are not develeoped! (laughing at self - Vote for Pedro).

Respectfully,

Matthew

Kaizen!

[vmcms]

Thanks. Maybe it's a limitation of my SAN but it does not support sharing a LUN twixt multiple initiators simultaneously.

Thanks to everyone!

[juchestyle]

Hey man,

Throw the stats out for you san, maybe someone out here knows what you need to do.

Respectfully,

Matthew

Kaizen!

[vmcms]

Thanks Matthew,

After some additional digging I think the correct answer is NFS. Multiple clients can connect to that and you can reach in and get vmx and vmdk files for backup.

The SAN is a StoreVault s500. The second most confusing graphical UI's with which I have ever worked. There is an FAQ in their support page that says you can't connect two hosts to a LUN simultaneously.

Any downside to NFS vs iSCSI? The SAN will do both.

Regards,

[juchestyle]

Hey man, go iscsi, no question. Contact your support about this, because I am willing to be a that you can. Perhaps it is in the terminology.

Respectfully,

Matthew

Kaizen!

[vmcms]

Why iSCSI vs NFS?

[ctfoster]

I'm not familiar with Storevault SAN but in principal they all work in a simliar way. Once the LUN is created you normally have to go through a process to ''allocate' the

LUN to specific IQN's which relate directly to initiator on the ESX host. Once the LUN is 'zoned in', a rescan on the ESX should reveal it.

From the point of the of the storage it normally doesn't care if you attempt to allocate two hosts to the same LUN - they normally just post a warning before you do it.

You need to look for this functionality on the SAN host.

[vmcms]

Here is a good comparison of NFC CIFS and iSCSI. iSCSI outperforms based on these results.