Hot swapping internal disk in rp4440.

[KRISH_7]

Hello!

I've a rp4440 running 11.11 (not patched for OLR)

One of the internal disks (0/1/1/1.0.0)which is part of vg00 is giving intermittent media error. This is the alternate mirrored boot disk and not the primary disk.

Can i replace this disk without shutting down the server since the disk is still accessible. ioscan, diskinfo shows disks is active and vgdisplay shows disk status is "available".

(I work in a sun shop. so my HP/UX expertise is minimal)

My plan:
1)Remove the mirror copy of all LVs on the failing disk. (lvreduce -m)
2)Remove the disk from vg00.
3)Identify the physical disk and hot swap the drive.
4) ioscan -fnH H/W path to see the replaced disk.
5)diskinfo /dev/rdsk/c3t0d0
6)pvcreate -B /dev/rdsk/c3t0d0
7)vgextend vg00 /dev/dsk/c3t0d0
8)mkboot /dev/rdsk/c3t0d0
9)mkboot -a "hpux" /dev/rdsk/c3t0d0
10)lvextend -m 1 all LVOLS
11) lvlnboot -R /dev/vg00


Will the above plan work? or do i need to take an outage to swap the disk?

Any comment/info/advice would be most appreciated..

TIA

[Jaime Bolanos Rojas. · Accepted solution]

Krish,

There is a relly good document on replacing a how swap, root hard drive that is mirrored in the ITRC site:

Document ID: LVMKBRC00006111

Please go throught the document,

Regards,

Jaime.

PS. Your plan looks right to me.

[DCE]

Yes, The above plan will work.

No you do not have to take an outage.

I just did a disk replacement on a rp4440 last week using the steps you listed

You can also try vgcfgrestore and vgsync which is a bit simpler and uses fewer commands (but for the disk failure I had, did not work)

[Torsten.]

Hi,

this is a very important command:

pvchange -a n /dev/dsk/...

see all the details here:

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

[Torsten.]

BTW, the disk

0/1/1/1.0.0

is the lower disk in duplex scsi configurations.

[MHudec]

Krish, two notes:

4) ioscan -fnH H/W path to see the replaced disk

- use ioscan -fn > /dev/null and then ioscan -fnkH HWpath, as -fnH might show inaccurate data sometimes (CLAIMED instead of NO_HW etc.)

9) mkboot -a "hpux" /dev/rdsk/c3t0d0

- might be good to use "hpux -lq" if you have two disks only in your vg00. With quorum restrictions you will need to override quorum to activate the volume group (while rebooting if you will need one as the system will panic then with lvm error message, but you say that you will hotswap the disks, so no reboot here in your case).