The next idea is checking the VGDA, it might just be corrupted.

If this is the case, you might have to repair the VGDA data, which is not an easy task (and without danger neither).

There is an (undocumented! so use at your own risk) command "readvgda". If used on a good copy it will show you the complete VG layout, including LVs, their PP mappings, etc.. I suggest you read also the LVM redbook to understand the concepts behind the following actions. CAUTION: these actions have the potential to harm your data, carefully examine all the steps, save everything you do and only proceed when feeling comfortable!

You need a "/etc/filesystems" too, because you do not get the mount points from the VGDA.

Now construct map files for each LV from the VGDA info. Then export the VG and recreate it on the original PVs and with the original PP size, then recreate each LV usin the constructed map file on its original place:

Code:

mkvg -f -y <VGname> -s <PPsize> <hdisk_dev_1> <hdisk_dev_2> ...
mklv -y <LVname> -m /path/to/mapfile -t jfslog VGname <numlp>
mklv ...

(I was supposing jfs here, change the commands accordingly if you use jfs2.)

Now restore the "/etc/filesystems" but DO NOT MOUNT yet!

For each filesystem update the LVCB with the log and label information:

Code:

chfs -a log=<logdevice> <mountpoint>
chlv -L <mountpoint> <LVname>

NOW run "fsck" over each FS - WITHOUT the "-y"! If "fsck" complains about not being able to read the superblock the respective LV was not recreated correctly and you have to start over. If the jfslog LV was not recreated correctly, then "fsck" will not be able to replay the log and you will probably lose some data, so better double- and triple-check your mappings before you answer "yes" to any of "fsck" questions if it should correct anything.

Note, that if a filesystem was online at the time of the crash fsck might find some (unrecoverable) errors because of corrupted inode-lists. The only thing you can do is to fix this, but it will probably make you lose data. (Serves you right if you have no working backup.)

Re-run "fsck" until there are no errors any more to correct, then mount FSes. If any errors were fixed you should check "lost+found" for the remains of orphaned files/blocks. You might be able to regain some of the lost data from there.

I hope this helps.

bakunin