Check /var/log/messages for I/O errors on sdb.Stuart, no offence can be taken ar all - I cam see two possibilities - u did smth very stupid or its a glitch.
I actually selected "shutdown" option in kde.
I cant say that fsck fixed - it reported a short read. I got completely shocked and just for the hell of it ran la just to observe that. Everything is "back".
If sdb1 had been the extended partition, then it overlaps both sdb5 and sdb6, so that building a PV/filesystem on sdb5 would overwrite the existing filesystem on sdb1. That would have come under the "very stupid" category. (I.e. don't try to add sdb2 as a PV! Does EL5 prevent this somehow? I don't have anything expendable attached to test on...)Since then I copied all files. To backup lv and ran that fack. Last reported no problem.
You mentioned something about extended partitions?