topic Re: expanding a virtual disk in EVA storage in HPE EVA Storage

expanding a virtual disk in EVA storage

radi_1 — Sun, 07 Nov 2010 08:19:35 GMT

Hi,
I have the following vitual array situation in a customer's EVA storage:
1-The default vgroup needs to be expanded by
adding new disks to it.
2-the vgroup has vdisks configured and presented to two HP-UX servers.
3- Each vdisk needs to be expanded to increase
capacity.
What are the steps needed to do the above,specaily task 3.
Note:
I could not find an option in command view which would allow me to expand a particular vdisk to new size ,but I read in a practice handbook that I need to UNPRESENT the vdisk before expanding it .Even in hp manuals there is no mention of such a task.
Please your quick advice would be higly appreciated.

Re: expanding a virtual disk in EVA storage

Jan Soska — Sun, 07 Nov 2010 22:12:10 GMT

hello,
1) if you have empty space inside vgroup, just resize it in windows showing size (e.g. 300GB -> 400GB) and save, it will extend vdisk
2) if there is no free space, you have to add disks into vgroup, ideally wait due leveling and go to step 1.

Most important - you OS must handle such change correctly, I think HP-UX is capable of it, but you need unix gui with knowledge of hp-ux tools hove to expand filesystem after you resized vdisk presented to server.

Jan

Re: expanding a virtual disk in EVA storage

Sheldon Smith — Mon, 08 Nov 2010 14:58:19 GMT

EVA virtual disks or "vdisks" are presented as LUNs to HP-UX.
Once HP-UX finds them, each vdisk becomes a Logical Volume Manager (LVM) Physical Volume. (pvcreate)
Multiple Physical Volumes become a (LVM) Volume Group. (vgcreate)
Volume Groups are sliced into (LVM) Logical Volumes. (lvcreate)
Logical Volumes *can be extended*. (lvextend)
And the majority of HP-UX systems I see, customers use LVM instead of creating a file system on individual EVA vdisks.

So where you say "the vgroup has vdisks configured and presented to two HP-UX servers", are you using the Logical Volume Manager to consolidate vdisks into logical volumes which have the file systems?

------
Don't forget to rate the usefulness/quality of *all* responses to (all of) your question(s).

Re: expanding a virtual disk in EVA storage

Torsten. — Mon, 08 Nov 2010 19:05:27 GMT

Before doing *anything*, please tell what OS version you have.

Anything below 11.23 does NOT support LUN increasing!

The additional space in a vdisk will just be useless until you recreate the VG!

Re: expanding a virtual disk in EVA storage

Sheldon Smith — Mon, 08 Nov 2010 20:41:14 GMT

Torsten, don't versions below 11.23 support "lvextend"?

Re: expanding a virtual disk in EVA storage

Uwe Zessin — Tue, 09 Nov 2010 05:34:09 GMT

But the question was about increasing the EVA virtual disk (=PV/physical volume) which lives 'below' the VG/volume group. The LV/logical volume is an object 'above' the VG and the PV.

Re: expanding a virtual disk in EVA storage

Torsten. — Tue, 09 Nov 2010 06:22:00 GMT

"lvextend" comes into play much later.

First the LVM structure (the physical extend layout) must be extended to the additional space (the grown vdisk); this can be done using "vgmodify", which is not available lelow 11.23.

The workaround is to create a new vdisk and add it to the volume group.

Re: expanding a virtual disk in EVA storage

Sheldon Smith — Tue, 09 Nov 2010 17:19:22 GMT

Uwe, I thought so too, then I noticed the mention of "vgroups". So I don't know if the author is talking about working with EVA vdisks directly, or EVA vdisks in LVM vgroups.

Re: expanding a virtual disk in EVA storage

Uwe Zessin — Tue, 09 Nov 2010 21:44:24 GMT

Looks like M .Salah has used a bit wrong terminology when calling an EVA "disk group" a "vgroup".