Migrate RAID 5 to RAID 1

[Paokara]

Hello,

I have a Proliant DL380 G5 server, with Smart Array P400, 3 disks in RAID 5. I would like to migrate to RAID 1 using 2 drivers and leave the third as spare. Using the ACU utility i can migrate to RAID 0 and not to RAID 1, this is because i have 3 disks i assume.
If i first migrate to RAID 0, can i then migrate to RAID 1 using the two drives? Or do i have to recreate the Array? There must be a way to accomplish this?
Thanks!

[marcus1234]

are you doing this off line by booting from the cd or via windows ,

if you are in windows it may not allow live migration via the windows system as you might not have cache and battery , you can check if you have these in the array config utility

boot of proliant support pack software cd cd and do it off line



>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<
This is how we thank in the forum

http://forums11.itrc.hp.com/service/forums/helptips.do?#33

Enjoy:)

[Paokara]

Thanks for your reply! I have cache and battery, and i can migrate online from RAID 5 to RAID 0, the wizard says that if i migrate to RAID 0 i will use the space of the 2 disks and the space of the third disk will remain unused! I just hope that i can migrate from RAID 0 to RAID 1 using just the 2 disks and leave the third disk as spare!
Have you experiense with RAID 0?

[marcus1234]

raid zero is not raid really it stripes half the data on each disk if 1 disk fails you have nothing left it is only used for speed , nothing else , best avoid it


This is how we thank in the forum

hint >>>>>>>>>>>>
http://forums11.itrc.hp.com/service/forums/helptips.do?#33

Enjoy:)

[TTr · Accepted solution]

> this is because i have 3 disks i assume.
Yes you can not exclude disks during the raid migration.

> If i first migrate to RAID 0, can i then migrate to RAID 1...

No because all three disks would be converted to raid0 and you would still have the same problem.

Your only option now is to save the data, recreate the disks in raid1 and restore the data.

[kris rombauts]

Paokara,

as already mentioned you cannot migrate from a 3 disk raid5 to a 2 disk raid1.
If you look at it from a pure user data perspective, then this is quit clear because a 3 disk raid 5 will have a usable user data capacity of 2 disk in total and a 2 disk raid1 only offers a one disk usable user data capacity. So you only have half the capacity then needed to migrate data.


What the array wizard is showing you when you migrate the raid level from raid5 to raid0 is unused space that becomes available and this is equal to the capacity of one disk. However the raid0 is still spread over the 3 disks, not 2 disks....
So there is no way to remove one disk out of this raid array without loosing data.. so backup and restore is your only possibility.


HTH

Kris

[Paokara]

Thank everyone for your help! Indeed, i had to make a backup first, then delete RAID 5 and Re-create RAID 1 with 2 disks and mark the third disk als Spare. Then i restored the image and it works fine now!

[Paokara]

Thanks! My problem is solved as i mentioned earlier.