HPE Storage Users Group

Hi

I had a VV which was already exported to 3 ESXi hosts which are in a cluster. I have added a new 4th host to the cluster and I wanted to export the VV to this new host.

I exported the VV and selected all 4 hosts. This has resulted in the VV being exported twice to the original 3 hosts (each new export has a different LUN ID to the original) and it is exported once to the new host.

Clearly I have an issue now where I need to unexport the new LUN ID from the 3 original hosts.

Going forward when I have to attempt this export again, what is the best way to do it? If I had only selected the new host, would the VV have been un-exported from the original 3 and left me with just one export to the new host. Or would it have in fact just exported to the new host and kept the original 3?

Confused with no test lab.

Any advice much appreciated.

Cheers

You should really be using Host Sets and Virtual Volume Sets. Once you do that, you don't have to export new volumes, you just add them to a VVS that has already been exported to a Host Set.

For example:
You have 3 ESX hosts -- ESX1, 2, and 3. Create a host set ESXCluster1 with those 3 members. For storage, you have VV1, VV2, and VV3. Add those to a new Virtual Volume Set VVS_ESXCluster1. Export VVS_ESXCluster1 to ESXCluster1, choosing a starting LUN# that makes sense. If a while down the road you need more storage, create VV4 and add it to VVS_ESXCluster1. It'll automatically export to all hosts as the next sequential LUN#. If you expand the cluster itself, just add ESX4 to host set ESXCluster1, and it'll see all the same storage as the other members.

Something to keep in mind:
LUN #s need to be sequential with no gaps, so if you already have a LUN 5, exporting the VVS as LUN 3 would only give you the ability to export 2 LUNs (3 & 4).

Personally, I steer clear of vv sets, because I prefer to massage my vv configuration a little more than that allows.

That said, if you're using clusters, and you're not using host sets, you really should be. Almost all clustering requires a consistent storage presentation from node to node, and host sets make that happen quite easily. All the hosts in the set see all the vv's exported to the set with the same export characteristics, no questions asked. Adding a new host? Just add it to the set, and it gets all the VV's.

Ok, I thought that would be the suggestion.

So, what is the best/safest procedure to move from hosts to host sets without any disruption?

The best thing to do is create a Host Set that contains your hosts for a given cluster. Then export the VVs to the host set. When you add new hosts you just add them to the host set and the VVs are automatically exported to them the same as the existing hosts.

For you existing issue you need to go into the IMC and go to HOSTS then clik on the host with th duplicate VLUNs and in the bottom under Host Details select the VLUNs tab and under that the Active VLUNs and find the volume you want to remove. You will see the volume presented several times for each path back to the array controllers you have defined. CRight click any one of the paths and select unexport. On the next screen you will see all the paths for that volume ID presented which you should confirm is all you want removed. Click the button to unexport and you are done.