HPE Storage Users Group

Hello,

I am new to 3PAR having recently been put in charge of our 7400c and I’d like to know the proper way to remove virtual volumes and reclaim that space. This will be the first time I have deleted any Virtual Volumes and really want to make sure that I understand the process so I don’t accidentally screw something up. I’ve read all the available 3PAR documentation but would like advice on the best way to remove storage from hosts.

Here is my situation.

I have 6 Virtual Volumes in a Virtual Volume Set

The Virtual Volume Set is exported to 2 Hosts (These 2 physical servers made up a MS Cluster). However, there is a Host Set that includes these two hosts but it looks like the person in charge before me exported the VV Set to the individual hosts instead of the Host Set. These hosts have been powered down.

I believe what I need to do in the 3PAR Management Console is the following:

1. In Virtual Volume Sets, Right-Click the VV Set and select “Unexport”. This will "unpresent"
the Virtual Volumes to the hosts.
2. After the VV Set is unexported, right click on the VV Set and select “Remove”. This will
remove all Virtual Volumes in the Virtual Volume Set as well as the Virtual Volume Set itself.
3. In Hosts > Host Sets, right-click the Host Set and select “Remove” to simply delete the now
unneeded Host Set.
4. Compact the CPG to reclaim space.

Please let me know if I’m on the right track.

Thanks in advance to you 3PAR experts!

Danoman0man wrote:Hello,

1. In Virtual Volume Sets, Right-Click the VV Set and select “Unexport”. This will "unpresent"
the Virtual Volumes to the hosts.
2. After the VV Set is unexported, right click on the VV Set and select “Remove”. This will
remove all Virtual Volumes in the Virtual Volume Set as well as the Virtual Volume Set itself.
3. In Hosts > Host Sets, right-click the Host Set and select “Remove” to simply delete the now
unneeded Host Set.
4. Compact the CPG to reclaim space.

Please let me know if I’m on the right track.

Thanks in advance to you 3PAR experts!

You are wrong on 2 and possibly 3 ... These actions will only remove the set (or "group") and not the individual items included in the set/group.

A generic rule for 3PAR is that everything can be a part of everything (with some exceptions like remote copy)... One physical disk can be a member of mulitple CPGs, one VV can be a member of mulitple VV sets, one host can be a member of mulitple host sets.

So after removing the VV set, you need to remove the VVs.

If the hosts are decommissioned you would need to remove the hosts are the host set is removed as well.

Did you get these decoms cleaned up?

Export/Unexport is creating and removing "VLUN Templates". The template defines what VLUNs can be dynamically created when a host wwn logs in. Check for Active VLUNs first before un-exporting. Assuming your 2 hosts are offline, I would expect to see 2 VLUN templates, one per host, but 0 active VLUNs. If the hosts are online, I suspect you will have 2 VLUN templates AND 32 active VLUNs. Check the GUI to see your hosts in question have 0 paths, and there are no VLUNs for the VVs.

That said, general advise I give is only unexport, then wait a week to delete objects (VV, Host). I like to call this "a scream test". It's quick and easy for storage admin to re-export to the VV they didn't delete to the Host they didn't delete. It's harder to recreate LUNs the right size, and hosts with the right WWNs, and do a restore from backup. It sounds your servers have been offline for some time, so you may have the equivalent of a scream test.

Your steps 2 and 3 should tell you to remove the hosts from the host set before deleting the host set. Same for VVs in VVset.

Thank you both for the replies. I think I'll take Richard's advice on the scream test and wait a week after unexporting.

Now I just need to get the process down on paper to submit to Change Management.

Thanks again, I really appreciate your help!