Moving host between Storage Goups

Question

I would like to move an ESX host from one storage group to another storage group that already has ESX hosts, and move the attached LUN with it. I am wanting to do this on our CX3-20c FLARE 26. I have a single ESX host with one LUN attached in it's own storage group (used as a test environment at one time) and would like to move it with it's LUN into the storage group with all our production ESX hosts. That way the ESX host I want to move will be able to see all the other ESX hosts LUNs and vice versa.

What is the best way to do this?

Thanks

dynamox · Answer

should work, the new host will need to be added to the cluster plus be ready to re-register your VMs.

dynamox · Answer

can you shutdown the VMs ? Present the LUN from test SG to the production SG, shutdown VMs and storage vmotion then regular vmotion to the new cluster, that way you won't have to re-register them.

tkjoffs · Answer

Add the LUN to the Prod Storage Group.Rescan / Refresh on the ESX Prod Hosts to get the LUN to show.Move the Test ESX Server to the Production Cluster.VMotion the VM to the other hosts (put the test box in maint mode).Disconnect the LUN from the Test SG.Remove the Host from the Test SG.Add the Host to the Prod SG.Rescan / Refresh to make it see all the Prod/Test LUNs again.Take it out of maintenance mode.VMotion the test machine back to it.Keep it in the prod cluster or move it back to it's own cluster (does not really matter - your preference).Delete the old no longer used test SG to cleanup the SAN.Smile - everything stayed running. Ted

tkjoffs · Answer

You know, I am not 100% on that. I do this all the time with currently existing LUNs mapped to two different SGs, and don't have issues. I know that the LUN IDs can cause issues with RDMs and have run into that but I "think" the LUN IDs for ESX VMFS volumes are syncronized across the hosts. Good question. If the VMotion failes he would have to shutdown the VM and bring it back online on the other cluster. Hmm. I guess the only way to know for 100% is to try. In my case I add LUNs to all SGs in order so the LUN IDs should all match.

TJ

tkjoffs · Answer

Actually, I lied.&#xa0; A little sleepy here. &#xa0; You CAN VMotion between clusters NOT data centers.&#xa0; So make sure your clusters are in the same data center and you are good.&#xa0; If not you need to do Line 3, else you can skip it.

tkjoffs · Answer

No, you can't.&#xa0; I have line 3 there to have him move the test ESX server to the production cluster (you can do that online via drag and drop or disconnect/remove and reconnect).&#xa0; Hope that makes sense.Note:&#xa0; Make sure you know the root password. Ted

dynamox · Answer

Are you sure you can vmotion between two different clusters online ?

dynamox · Answer

you don't think he will need to re-register VMs ? The old LUN will most likely be assigned new host id .

aubman · Answer

Thanks guys for the responses. We ended up doing a similar process to what tkjoffs posted.

1. We connected the LUN to the Prod Storage Group and did a rescan in VM

2. VMotioned the active VM servers from the test ESX to prod ESX cluster (probably didn't have to do this step but...)

3. Moved the test ESX to the Prod Storage Group...did this by just adding the host to the Prod Storage Group and letting the Navisphere remove it from the other Storage Group (host can't be in two SGs)..not sure if this was the best way but I had seen that someone else had gone that route for something else.

4. Removed the LUN from the test Storage Group

5. Did a rescan in VM...all the LUNs were presented

6. Added the ESX server to the prod cluster

Everything went smoothly.

CLARiiON

Moving host between Storage Goups

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