topic Re: RSS state mirrored in Disk Enclosures

RSS state mirrored

Walter Sklenka_1 — Mon, 05 Nov 2007 15:23:52 GMT

Hello!
I am quite new to eva products, and sorry for my bad english :-) )

Our customer has foolowing bad scenario:
He has one diskgroup with 8x73GB and 6x300GB mixed.

We want to add 6x 300GB disks and 8x73GB. And while this split them into 2 disk groups:

So I would add 6x300GB to the old disk group, and consecutively remove one 73Gb disk after the other, till there are only 12x300GB disks in the old diskgroup.

Following is the prereqisite: We install a second disk shelve, and the customer wants 2 vdisks available in the event of failing one shelve (about the other vdisks he does not care)

So now I would create a new disk group with 4x73GB in first shelf and 4x73GB in the second shelve.

And linux-dd the data of the two vraids to the new diskgroup YY.

My question is:
Does the allocation 4+4 disks automatically grant, that the vraids are still available, when one shelve fails?

I have read in this forum that the RSS state needs to be "mirrored". Does this occure without user-intervention, or do I need to change something?

I hope someone understands my a bit confusing question and scenario?

Thanks a lot in advance for any help
walter

Does it make sense, that

Re: RSS state mirrored

Uwe Zessin — Tue, 06 Nov 2007 13:31:47 GMT

The RSS allocation code does not always work properly which means that you might need to physically move disk drives after a change, although there is a good chance it will do it right with a new disk group.

I've been told that the RSS state is no longer shown :-(
While I have done a few installations with CV-7, I must admit that I have not verified it myself, yet.

Re: RSS state mirrored

Walter Sklenka_1 — Tue, 06 Nov 2007 14:32:25 GMT

Hi Uwe!
Thanks a lot for the reply!

Do you know, if there is an other method to verify that the disk group is mirrored over both shelves?

best regards

Re: RSS state mirrored

mmax — Wed, 07 Nov 2007 05:44:18 GMT

Hi.
It's possible to check RSS state from sssu.
BR

Re: RSS state mirrored

Uwe Zessin — Wed, 07 Nov 2007 06:07:37 GMT

EVA> ls disk_group full

Disk_Groups available on this Cell:
\Disk Groups\Default Disk Group information:
object
...
rssdiskstate .: none

It's a 2C4D - I have read here in ITRC forums that XCS does no longer report the state :-(
but I don't have time right now to run my own RSS analyzer on this data to verify this.

Re: RSS state mirrored

mmax — Wed, 07 Nov 2007 06:56:22 GMT

CV-7 doesn't show RSS state. SSSU show status. because RSS state is dependent on mirror pair disk distribution (dependent on RSS ID) you can analyze your status and swap disks to have right RSS state.

Re: RSS state mirrored

Uwe Zessin — Wed, 07 Nov 2007 07:33:54 GMT

I meant XCS when I wrote XCS, not the CV-EVA GUI.

Re: RSS state mirrored

mmax — Wed, 07 Nov 2007 10:59:16 GMT

sorry I missunderstand that

Re: RSS state mirrored

Uwe Zessin — Wed, 07 Nov 2007 14:14:03 GMT

No problem. I've found the thread I mentioned above:
http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1132836