Mirrored disk.....

UNIX AIX
1

How do I know, which all disks are mirrored? any command?

Bala

2

I AIX usually not disks are mirrored, but logical volumes.

Issue "lsvg -l <vgname>" and note the number of PPs and LPs each LV takes: if the number of PPs is double the number of LPs on mirror exist (every LP exists in 2 copies on two different PPs), asf.

Here is a sample output to give you the idea:

# lsvg -l rootvg
rootvg:
LV NAME             TYPE       LPs   PPs   PVs  LV STATE      MOUNT POINT
hd5                 boot       1     1     1    closed/syncd  N/A
hd6                 paging     9     9     1    open/syncd    N/A
hd8                 jfs2log    1     1     1    open/syncd    N/A
hd4                 jfs2       1     2     2    open/syncd    /      # <-- this is mirrored
hd2                 jfs2       70    70    1    open/syncd    /usr   # <-- not mirrored
hd9var              jfs2       16    48    3    open/syncd    /var   # <-- two mirrors

bakunin

3

Thanks Bakunin....

4

But Bakunin.. I suppose you can mirror a disk in AIX 5.3.
Suppose I want redundancy for my rootvg.. what I normally do is add a physical disk (PV) to the vg, mirror it and then make the second disk bootable using the "bosboot" command. Now my question is how will I come to know which all disks are mirrored like this...

Balaji...

5

I can help you a bit...

take the output of lsvg -l rootvg...and with bakunin's reply u can find out the file systems which are having 2 PPs for their LPs.

Now search for those file systems(which are having 2 PPs for their LPs) on each HDD in that VG. If you find the File system. that PV is in the mirroring.

6

Hi Manu,

Thanks for that Idea.. i was also thinking for that..thanks a lot.

cheers...

Bala

7

when u give lsvg -l rootvg u can find whether the FS is mirrored ....
lsvg -l rootvg
rootvg:
LV NAME TYPE LPs PPs PVs LV STATE MOUNT POINT
hd5 boot 1 2 2 closed/syncd N/A
hd6 paging 141 282 2 open/syncd N/A

then if u give lsvg -p rootvg ,it gives what r all the disk r belong to VG,
lsvg -p rootvg
rootvg:
PV_NAME PV STATE TOTAL PPs FREE PPs FREE DISTRIBUTION
hdisk1 active 542 1 00..00..00..00..01
hdisk2 active 542 1 00..00..00..00..01

still if u want to know more in which hdisk and which pv here is the command,conclusion that Hdisk2 is the mirror of hdisk1

lslv -m hd1
hd1:/home
LP PP1 PV1 PP2 PV2 PP3 PV3
0001 0041 hdisk1 0041 hdisk2

8

Wow.... That what was I was looking for..

Cheers..

Bala