topic Re: recovering Data in Operating System - HP-UX

recovering Data

himacs — Mon, 24 Aug 2009 10:54:37 GMT

Hi Admins,

Let me tell the scenario..

One of my server is down..and has 1HDD with some data..
i want to recover the data
since server is down , vgexport/import is not possible..

how can i recover the data with connecting to another server..

Actually this is not happened,one of my friend asked the doubt..

Regards,
himacs

Re: recovering Data

Pete Randall — Mon, 24 Aug 2009 11:04:04 GMT

If you can attach the HDD to another server, it can be vgimported - there is no need to vgexport prior to vgimport.

Pete

Re: recovering Data

Torsten. — Mon, 24 Aug 2009 11:05:07 GMT

Was the disk configured with LVM? Was this disk the only member of a certain VG? If yes, connect it to another server and use vgimport.

Re: recovering Data

himacs — Mon, 24 Aug 2009 11:08:47 GMT

Hi Pete,Torsten

Thanx for the reply..

<>

Plz tell me the exact steps to be performed..

If that HDD has VG00 and existing one also having VG00..how to proceed..

regards
himacs

Re: recovering Data

Ganesan R — Mon, 24 Aug 2009 11:10:35 GMT

Hi Himacs,

If you are connecting the HDD to another server, the only concern is device file get changed.

What you need to do is, boot the server into maintanance mode, export the root VG and reimport it, which will import the VG with new device files.

Re: recovering Data

Ganesan R — Mon, 24 Aug 2009 11:22:46 GMT

Hi Again,

Look at this document. "Appendix J" gives the exact steps you need to perform for this activity.

http://docs.hp.com/en/5991-1236/When_Good_Disks_Go_Bad_WP.pdf

Re: recovering Data

himacs — Mon, 24 Aug 2009 11:31:39 GMT

Hi Ganesan,

Thanx for the reply..

<<7.
To create the volume group and the group file to be used for the vgimport command, enter: # mkdir /dev/vg00 # mknod /dev/vg00/group c 64 0x000000

OK.. let me explain the scenario again..

The new server already has VG00..etc
I want to recover the data from HDD of old server(which is down now) with connecting to new server..I dont want to use the HDD with new server.Just i want to recover the data..
And i dont have any /etc/lvmtab details of old server.

regards
himacs

Re: recovering Data

Mel Burslan — Mon, 24 Aug 2009 11:33:49 GMT

Himacs,

No, the VG you will import does NOT have to bear the same name as it was originally named. So, your vg00 coming from the dead server can be named as any vg on the running system. Make sure the vg name/number is unique on the new and running server.

mkdir /dev/vg09 # assuming vg09 did not exist
mknod /dev/vg09/group c 64 0x090000
vgimport /dev/vg09 /dev/dsk/cXtXdX # modify cXtXdX according to your condition

since you will not have a mapfile, the logical volumes may ne named randomly but the contents of these volumes should still be in there. It is just a game og hunt and peck from this point on.

Re: recovering Data

Ganesan R — Mon, 24 Aug 2009 11:46:29 GMT

Hi Himacs,

We understood the scenerio now. You want to to connect the root HDD to another running server and want to recover the data.

1.Connect the HDD
2.#ioscan -fnC disk
3.#insf -e -v (if need)
4.#mkdir /dev/vg00old
5.#mknod /dev/vg00old/group c 64 0x090000(assuming 0x090000 not being used already)
6.#vgimport /dev/vg00old 7.#vgchange -a y /dev/vg00old
8.#vgdisplay -v /dev/vg00old
9.#mount

Hope this helps...

Re: recovering Data

himacs — Mon, 24 Aug 2009 11:51:19 GMT

Hi Ganesan,Mel..

Thanx for ur response..

So no need to go LVM maintenance mode..

After connecting and rebooting we can perform the steps..

regards
himacs

Re: recovering Data

Torsten. — Mon, 24 Aug 2009 11:53:05 GMT

Online or not - it depends on how do you connect the disk. If you need to open a SCSI bus you should do this offline.

Re: recovering Data

Mel Burslan — Mon, 24 Aug 2009 13:20:38 GMT

If you can connect the disk drive to the running server while it is running, then fine, you do not need to offline the system or go into lvm maintenance mode. But If you are going to shut the server down to attach the drive, it might be a good idea to boot into lvm maintenance mode, although, for what you are doing, it is not absolutely necessary.

Re: recovering Data

himacs — Mon, 24 Aug 2009 14:50:59 GMT

Hi All,

m overhelmed with ur responses..

Thanx for the support..points assigned

regards
himacs