Moderator's Comments:

This is a problem directly related to AIX and we have special forum for AIX. I am going to move the thread there.

Your notes are correct, but only for working disks. Because it is not clear how the copies in your VG are set up it might well be that you have already lost data.

A word about that first: as a responsible admin you should never, NEVER let 3 disks become missing! You should act immediately when the first one fails. This usually foreshadows in the "errpt", when a disk issues an increasing number of disk errors (usually hdisk error 3, which is temporary). What happens there is that blocks are becoming bad and are relocated to good sectors. When formatting a disk AIX sets aside a number of such contingency sectors. One by one these are used if a sector becomes bad but at one point they are exhausted and then you usually get a hdisk error type 4, which is permanent. I suggest to check the "errpt" and "errpt -a" output respectively to find out what happened to the disks.

Second: take stock of your data. Find out if you still have a good copy of every LP (logical partition) by generating a map file for each LV. When you mirror a LV two (or even three, depending on the number of mirrors) PPs are representing one LP. Check the map files for all the LVs if there are LPs represented only by PPs from hdisk31 or hdisk3. If so, you have lost data and you will have to restore its contents from backup (you do have a backup, don't you??).

You will need to varyon the VG for that. Alas, it will not work when disks are missing, even if the quorum checking is disabled. Use the "force" option for this, also use the "-r" option to varyon in read-only state and the "-n" to disable synchronisation of stale partitions:

Code:

varyonvg -fnr vg_usr1

Now generate the map files for analysis and varyoff again:

Code:

lslv -m <LVname> > /path/to/file

What comes now depends on what your analysis results in. In case you have not lost data already you can try immediate removal of the failed disks. Varyon again and remove all the missing disks:

Code:

varyonvg -f vg_usr1
reducevg -df vg_usr1 hdisk3
reducevg -df vg_usr1 hdisk31

Now try to settle the system:

Code:

synclvodm
varyoffvg vg_usr1
varyonvg vg_usr1

The last one has to work without any "brutal" handiwork: without "force"-options or the like. If this works so far you might try to put hdisk42 to work. Tell us how far you got and i will explain how to do that in a separate post.

I hope this helps.

bakunin