EMC migration and pmove command

[Colomoto]

Hi guys,

We have to migrate from one EMC to another EMC(data). We are going to present the new disk from EMC_NEW to out server. Then we are going to create physical volumes for the new VDISKs and add them to the vg containing the data to migrate. The question is: Is it safe to issue the pmove between older and newer disks?.
Do you know a better aproach to this?.
Any procedure out there from HP?.

Regards,

Sebastian

[Michal Kapalka (mikap)]

hi,

the question is if you can have a downtime,

if yes create a new VG's with the new LVOL-s and use dd to offline copy of the data, them use lvextend to extend the NEW Lvol-s ( if the size is bigger as the OLD one, and them fsck for the LVOL.

or use LVM ( mirroring of the data ), them you could reduce the old disk from VG.

for each problem/task are several procedures/solutions , but its up to which is the best for your company related to the downtime/impact for you business.

mikap

[Torsten.]

If 11.31, consider to use

vgmove

http://docs.hp.com/en/16179/vgmove-wp.pdf

[Colomoto]

Hi all,

Thanks for the reply. What about pmove. I´m not using 11.31 and the downtime is not possible right now.

Do u think it is a safe solution?
From support they told me that pvmove do a mirror and the when all the information has been copied to dest, the mirror is broken. After that we have the PE moved to the dest. Do u thing that this is a good solution?

Best regards,

Sebastian

[Robert-Jan Goossens_1]

Hi Sebastian,

What about replication between the EMC boxes? EMC has tools to replicate the data to the new storage box depending on what kind of SAN you have.

An other option is to mirror your data to the new SAN, but you will need the MirrorUX license from HP.

Regards,
Robert-Jan

[Olivier Masse]

pvmove is "safe", I use it all the time to reorganize storage on the same disk array. But if you can, I think an LVM mirror is even more robust -- it lets you integrate the new array slowly and provided redundancy if there is every trouble. When you're ready to switch, just lvreduce the PVs from the old tower.

I have not gone through this yet but will soon, and an LVM mirror will probably be how I will do it.

Good luck

[James R. Ferguson]

Hi Sebastian:

> What about pmove. Ià ´m not using 11.31 and the downtime is not possible right now.

Using 'pvmove' would not be my choice. Should any interruption occur when the process is running, your logical volume may be left in a stale state --- rather a mess.

If you don't care about replicating your current LVM geometry then use MirrorDisk/UX if you have it.

Otherwise, as Robert noted, EMC has SAN replication software that will probably accommodate your needs.

Regards!

...JRF...

[Colomoto]

Hi all,

As I ran out of time and I didn't have to much time to spend with the Storage guys (good people with not time :) ) I issued the pmove... all finished fine.

Thanks all for your knowledge.

Next time I will try Mirror or EMC tools instead, just for try other solutions.


Regards,

Sebastian

By the way HP Support told me that the pmove command mirror the disks and after PE movement, break the mirror... so I don´t know why the disk should be in stale status if the copy suddenly finished. Maybe I can test it and disconnect the dest with a scsci disk. I think that the behaviour should be the same for a VDISK. What do u think, have u ever tested it?


Regards,

Sebastian