topic Re: Virtual array 7400 in Disk Enclosures

Virtual array 7400

Olga_1 — Wed, 21 Aug 2002 13:57:47 GMT

Is it possible to configure VA7400 for RAID 5?
Thank you.

Re: Virtual array 7400

Sajid_1 — Wed, 21 Aug 2002 14:01:25 GMT

Yes ..ofcourse!

Re: Virtual array 7400

Sajid_1 — Wed, 21 Aug 2002 14:02:22 GMT

Check here:
http://www.hp.com/products1/storage/products/disk_arrays/midrange/va7400/overview/index.html

AND here:
http://www.hp.com/products1/storage/products/disk_arrays/midrange/va7400/index.html

Re: Virtual array 7400

harry d brown jr — Wed, 21 Aug 2002 14:07:11 GMT

It is raid 5 with dual parity.

http://www.hp.com/products1/storage/products/disk_arrays/midrange/va7400/infolibrary/index.html

live free or die
harry

Re: Virtual array 7400

A. Clay Stephenson — Wed, 21 Aug 2002 14:10:44 GMT

The best answer is not precisely. The VA's use RAID5DP which is striped data with two parity blocks. You can run your VA in AutoRAID mode which dynamically balances RAID 1/0 for good performance with RAID5DP for better cost per unit of storage. AutoRAID keeps the most recently used data in RAID 1/0 and less frequently accesses data is migrated to RAID5DP.

Re: Virtual array 7400

Olga_1 — Wed, 21 Aug 2002 14:14:04 GMT

That the thing. They bought it to replace auto raid. The want it to configure for RAID 5

So the answer: it is not possible?

Re: Virtual array 7400

harry d brown jr — Wed, 21 Aug 2002 14:18:20 GMT

It is raid 5 with dual parity, meaning that there are two parity drives, this actually covers you if you lose two disks.

live free or die
harry

Re: Virtual array 7400

Sajid_1 — Wed, 21 Aug 2002 14:28:26 GMT

Hello,

It's works on RAID-5. The *shifting* of data from RAID-5 to RAID-1/0 and the reverse has been done by the RAID controller. This is for making the array, more relaible and faster.

You could say that it works on RAID-5!

Re: Virtual array 7400

Olga_1 — Wed, 21 Aug 2002 14:43:52 GMT

I am sorry , I so not know much about it, but how its diferent from AUTORAID?

Re: Virtual array 7400

Sajid_1 — Wed, 21 Aug 2002 14:59:52 GMT

I know what do you mean now. This may answer your question:
Is RAID-5 supported? - Yes.
Is AUTORAID supported? - Yes
Is RAID 1+0 supported? - Yes

Can you configure it *only* for RAID-5 (pure RAID-5, no AUTORAID) - NO.

Can you configure only for AUTORAID or RAID 1+0 - Yes.

hth,

Re: Virtual array 7400

Sajid_1 — Wed, 21 Aug 2002 15:03:11 GMT

Here you go: A same type of question asked in VA7400 FAQ:
http://www.hp.com/cgi-bin/cposupport/get_doc.pl?SNI=hpsurestor43759&LC=information_storage&Tfile=lpg35043

Re: Virtual array 7400

Olga_1 — Wed, 21 Aug 2002 15:04:13 GMT

Bingo! This is what I need it. Thank you very much.

Re: Virtual array 7400

Tim D Fulford — Wed, 21 Aug 2002 18:26:09 GMT

Just a iggly niggly thing, RAID 5 with dual parity is RAID 6!!! HP for some reason decided to call it RAID5-DP

I know this is splitting hairs but it makes a massive difference when it comes to mean times between falure. Effectively you get two things
1 - much larger RAID groups with acceptable MTBF (longer stripe)
2 - IF one disk fails you do not need to have a high priority rebuild as you still have one more failure to go

The only "down" side is that you need two extra disks instead of one.

just mu 0.02???

Tim

Re: Virtual array 7400

Vincent Farrugia — Wed, 21 Aug 2002 18:43:24 GMT

Hello,

On the VA, there is no RAID-5. It's RAID-5DP, which means "dual-parity". What it actually does is that you can have TWO disks failing and still no data is lost. RAID-5 only supports ONE disk failing, if TWO fails, the entire LUN is lost.

That is it basically.

HTH,
Vince