How to remove disk from mirror?

UNIX AIX
1

Hello,
I've got 2 system disks (hdisk0 and hdisk1) in the mirror (RAID1) on AIX 5.3. Since the hdisk1 makes some troubles, we want to replace it with the new one. How can I disable this hdisk1 disk and prepare the mirror to use the new physical disk? As far as I know, I must remove disk from the volume group, but what more to do?

TIA,
Yac.

2

use

#smitty vg

->unmirror a volume group

choose rootvg and hdisk1 to remove

then

reducevg rootvg hdisk1

or smitty vg

-> Set Characteristics of a Volume Group -> Remove a Physical Volume from a Volume Group

3

Thank you! In meantime I have read somewhere that the reducevg command can fail when there are not mirrored areas on both disks, for example when sysdump area is not mirrored. I have seen that our sysdump area is unfortunately not mirrored on hdisk1, so I think the reducevg command will fail. Should I first create a secondary dump device on hdisk1? But it probably will not work since hdisk1 is out of order.. What to do in this case?

Yac.

4

if the volume is not mirrored on hdisk1, it remains on hdisk0 - so wheres the problem?

check lspv -l hdisk1 to make sure

reducevg fails if there is still a lv on the disk, but it will not continue to remove, so you can try without risk

if you just want to replace the disk:

migratepv hdisk1 newdisk

then do
bootlist -m normal -o hdisk0 newdisk
(extend the command with other boot-devices you use, such as cdrom)

bosboot -a

make sure the new disk is bigger or equal to hdisk1

migratepv will not work, if hdisk1 is unreadable somewhere