reinstalling hpux w/o disturbing oravg

[Santanu Bhadra]

All:

I have a L3000 server running hpux 11.00.

The vg00 is on /dev/dsk/c1t2d0 and has all
standard LVs (/tmp, /usr, /var etc.)in it.

The second VG is oravg which has 8 LVs for
oracle stuff. This oravg includes the
following disks.
/dev/dsk/c1t0d0
/dev/dsk/c2t0d0
/dev/dsk/c2t2d0

I am planning to reinstall hpux from scratch
without disturbing oravg; And I should be able
to use all the oracle LVs after reinstallation
without any problem.

Here are the post-installation steps I have
in mind.

a. create a oravg directory in /dev
b. mknod c /dev/oravg/group 64 0x01000n
and I will use 0-9 for n; I have already noted
the details of all the device files in there.
c. vgimport -v /dev/oravg /dev/dsk/c1t0d0
/dev/dsk/c2t0d0 /dev/dsk/c2t2d0
d. vgchange -a y oravg
e. create the mount points with proper permissions
and mount the logical volumes of oravg

Please suggest me any addition/modification.

Thanks to all in advance!

Regards,
Santanu

[Scott Van Kalken]

looks good to me.

Perform a vgcfgbackup and a vgexport before hand just to be on the safe side.

Makes the import easier as well.

[Michael Tully]

Hi,

Make sure that you run a vgexport in preview mode. Even though you are trashing to whole operating system, make two backups. Once being a full system backup and the other an ignite backup. You may need these just in case you forgot to keep something you may want later.

-Michael

[Jason VanDerMark]

The first thing that I would suggest it to ensure that you have a good backup. Make a backup of the oracle info and then do a test restore to ensure that the media is good. Then make a map file of the oracle vg (vgexport -p -m /tmp/vgora.map). FTP the map file over to another server. Then bring down your box and reinstall hp-ux. Once the install is complete, retrieve the map file from the remote system and then mkdir your vg's directory and mknod your group file as you have stated above, except you don't need to worry about the lvols. Once you have the group file and directory created, it's time for the import(vgimport -m /tmp/vgora.map /dev/vgora /dev/dsk/cxtxdx...)This should take care of everything except for mounting the drives and adding entries into the /etc/fstab so that your new lvols will mount on boot. I hope that this helps. Good Luck.

Regards,
Jason V.

[Jason VanDerMark]

oops the commandline for creating that map file should have been:

vgexport -p -m /tmp/vgora.map vgora

Sorry about that.

Regards,
Jason V.

[Volker Borowski]

Hi,

be VERY careful.
As you can see, you have two controllers in this machine ! Now if the second one has been installed AFTER the OS has been installed, it might be , that you will switch LUNs upon re-install !!!!

-> HW Adress 52..... c1t6d0 Primary disk
-> later added HW Adress 40.... c2t6d0 Oracle disk

Now if you install UX from scratch, HW 40... will become LUN 1 because of lower hardware path, means if you select c1t6d0 for reinstall, you will right then wipe out your oracle disk !

Make sure you have a VERIFIED backup of your oracle filesystems available.

Good luck
Volker

[Carlo Henrico_1]

Backup, backup, backup.

I have just lost my root disk 3 days ago...no vg maps etc. What I did was the following:

After replacing the root disk and installing UX again as well as Omniback:

Restored from backup the /dev/vg** (except /dev/vg00) as well as my /etc/fstab and /etc/lvmtab

Then I did the vgchange -a y ... and a mountall and fsck.

All my data, database, 3rd party software etc was still there, the bad part was the links on the root disk to certain software, and of-course my swlist I am not sure how to fix yet - eventhough Oracle and MQSeries works (after I also restored the links) the swlist does not know about these products!!!

Good luck

Carlo

[Carlo Henrico_1]

PS: Remember the kernel parameters. I suggest doing a kmtune and send the output somewhere to assist in setting the parameters again after re-installation, in particular for Oracle!!!

Cheers

Carlo

[Wodisch]

Hello Santanu,

use the "vgexport" with the options "-m" (for the map file) and "-s" to get the VG-id included.
Then you'll have to save that file on another station, and then you can use it on the freshly installed machine with
"vgimport -m YOURMAPFILE -s /dev/vgora" and NO disk devices - it will search for those on its own (hence you do no have to care about controller instances!).

HTH,
Wodisch