how to migrate hp-ux data from san to san? (1333 Views)
Reply
Regular Advisor
Peter A. Berger Jr.
Posts: 108
Registered: ‎09-19-2001
Message 1 of 9 (1,333 Views)
Accepted Solution

how to migrate hp-ux data from san to san?

HP-UX 11.11 guru's: I'd like to bounce the following ideas through the forum to see if this is the safest/best way to migrate data from a SAN array (EMC CX-700) to a new SAN disk array (HP EVA-8000) using MirrorDisk/UX?

Comments/verification/tips, etc. would be great and helpful! thanks...

1. # swlist | grep -i mirror
Yes. I do have MirrorDisk/UX installed.

2. Run a tape backup before proceeding.

3. #lvdisplay -v /dev/vg03/lvol1
To see LV's MB size and # of PE's allocated.
PV = /dev/dsk/cAtB/dC

4. Create and present EVA LUN to host with same MB size and PE's as existing EMC LUN. (ioscan; insf -e; reboot if necessary to see HP LUN).

5. # lvextend -m 1 /dev/vg03/lvol1 /dev/dsk/cXtYdZ
where cXtYdZ is the new EVA LUN. This should mirror the data from EMC to HP SANs.

6. # lvdisplay -v /dev/vg03/lvol1
look for "mirror copies = 1"; "distribution of logical volume = 2 PV's (/dev/dsk/cAtBdC and /dev/dsk/cXtYdZ" and "logical extent status = current"

7. wait overnight to make sure mirrors are synced.

8. Shutdown Oracle DB and evict users.

9. # lvdisplay -v /dev/vg03/lvol1
Look for all LE's to be "current".

10. # lvreduce -m 0 /dev/vg03/lvol1 /dev/dsk/cAtBdC
which should break the original EMC-based LUN (/dev/dsk/cAtBdC) and only leave the HP-based LUN (/dev/dsk/cXtYdZ) for use.

11. # lvdisplay -v /dev/vg03/lvol1
look for "mirror copies = 0"; "distribution of logical volume = 1 PV's (/dev/dsk/cXtYdZ)

12. #bdf
if all looks OK - un-present EMC LUN to HP-UX host.

13. #ioscan

14. #insf -e

15. Start Oracle.
Please use plain text.
Honored Contributor
Sundar_7
Posts: 1,938
Registered: ‎11-07-2000
Message 2 of 9 (1,333 Views)

Re: how to migrate hp-ux data from san to san?

Peter,

Looks good except for couple of minor points

5 & 7 - lvextend will not return until all the extends are mirrored.

After lvreduce, you might want to vgreduce and remove the PV from the volume group before unpresenting the EMC-LUN to HP.

Good luck

Sundar.
Learn What to do ,How to do and more importantly When to do ?
Please use plain text.
Exalted Contributor
Steven E. Protter
Posts: 33,806
Registered: ‎08-15-2002
Message 3 of 9 (1,333 Views)

Re: how to migrate hp-ux data from san to san?

Shalom,

The really safe way.

Shut down the oracle database, back it up to tape. Restore it after the filesystem of the same name is rebuilt.

Using mirror/ux on a hot, running database will take a very, vary long time to complete and will adversely impact oracle througput.

Your plan however can work, if you don't mind miserable i/o performance during the mirror copy.

8. Shutdown Oracle DB and evict users.
Evict the users first, it makes the datbase much easier to shut down.

I like option 10, but wonder if it will work. I suggest trying it in the lab first. lvsplit is an alternative but I'm not sure if it gives you the control of which mirror remains.

14. insf -C disk
to detect disk. I see no reason for step 14.

SEP
Steven E Protter
Owner of ISN Corporation
http://isnamerica.com
http://hpuxconsulting.com
Sponsor: http://hpux.ws
Twitter: http://twitter.com/hpuxlinux
Founder http://newdatacloud.com
Please use plain text.
Honored Contributor
Zinky
Posts: 663
Registered: ‎11-26-2003
Message 4 of 9 (1,333 Views)

Re: how to migrate hp-ux data from san to san?

Peter,

I'm a battle scarred veteran of Data Migrations. The following is how I always do it for my clients. Over the years it saved them thousands on Data Migration Services and it is not disruptive.

1. Hook up your EVA8K to your SAN and present corresponding number/sizes of Vdisks/LUNs to your servers. Up to you if you want a one for one LUN presentation.

2. Once the EVA LUNS are seen, vgextend your DGs to include these EVA8K LUNs.

3. Over time, either use mirroring (lvextend/lvreduxe) or pvmove

4. Once all your Data are on EVA8K LUNs, ease out the EMC PVs out of the VGs and depresent your EMC LUNs.

5. Done.


If you were running VxVM, the more easier...

Hakuna Matata

Favourite Toy:
AMD Athlon II X6 1090T 6-core, 16GB RAM, 12TB ZFS RAIDZ-2 Storage. Linux Centos 5.6 running KVM Hypervisor. Virtual Machines: Ubuntu, Mint, Solaris 10, Windows 7 Professional, Windows XP Pro, Windows Server 2008R2, DOS 6.22, OpenFiler
Please use plain text.
Honored Contributor
Matti_Kurkela
Posts: 6,271
Registered: ‎12-02-2001
Message 5 of 9 (1,333 Views)

Re: how to migrate hp-ux data from san to san?

SEP, I too can confirm that the step 10 will work as intended. We've done several SAN migrations using this method.

The intent of step 14 is apparently to remove all those EMC disk device files that are now in NO_HW state, as the disks have been un-presented. A good practice, but I'm not sure whether "insf -e" will accomplish that or not.

I have written a small script (attached, 4 lines or so) to find the disk devices in NO_HW state and run "rmsf" on them.
MK
Please use plain text.
Trusted Contributor
Basheer_2
Posts: 571
Registered: ‎09-12-2002
Message 6 of 9 (1,333 Views)

Re: how to migrate hp-ux data from san to san?

Hi Peter,

I did this from VA7x00 to EVA-5000 online.

one thing you must be aware of is if PE's >= 65536

Read this doc ID 8606365604 for more information.
Please use plain text.
Regular Advisor
Peter A. Berger Jr.
Posts: 108
Registered: ‎09-19-2001
Message 7 of 9 (1,333 Views)

Re: how to migrate hp-ux data from san to san?

All -- thanks for the tips/help. I'll try it out on a test system and report back here.

per step #10 -- I even read the man page for lvreduce and was confused at the syntax.

# lvreduce -m 0 /dev/vg03/lvol1 /dev/dsk/cAtBdC

which "should" break/delete/remove the original EMC-based LUN (/dev/dsk/cAtBdC) and only leave the HP-based LUN (/dev/dsk/cXtYdZ) for use.
Please use plain text.
Honored Contributor
Sundar_7
Posts: 1,938
Registered: ‎11-07-2000
Message 8 of 9 (1,333 Views)

Re: how to migrate hp-ux data from san to san?

Peter,

Your lvreduce command will only remove the mirror extends from the EMC Lun. But the PV will still be part of the volume group.

So, when you are done migrating, you will need to run vgreduce to remove the EMC Lun from the VG before unpresenting them.

Sundar.
Learn What to do ,How to do and more importantly When to do ?
Please use plain text.
Regular Advisor
Peter A. Berger Jr.
Posts: 108
Registered: ‎09-19-2001
Message 9 of 9 (1,333 Views)

Re: how to migrate hp-ux data from san to san?

thanks for all your help/support on this thread. it worked just fine. ITRC rocks!
Please use plain text.
The opinions expressed above are the personal opinions of the authors, not of HP. By using this site, you accept the Terms of Use and Rules of Participation