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Lost system disk label !!

John Welsh_2
Regular Advisor

Lost system disk label !!

Hi all,
I have a customer who has inadvertently
zero'd the label on his system disk.
( Tru64 V5.1B ) He doesn't have a record of
any of the partitions in the label except
that he was using AdvFS. Is there by any
chance an AdvFS utility that can scan the
disk and work out start and end blocks of
AdvFS partitions ? I suspect that he has lost
it all.......Regards, JohnW.
3 REPLIES
Venkatesh BL
Honored Contributor

Re: Lost system disk label !!

Do you have any sys_check output? If the disklabel is stored somewhere, you would be able to re-write it.
Ivan Ferreira
Honored Contributor

Re: Lost system disk label !!

I think that this is a big problem, if it was the system disk, they have the a b g and maybe h partitions. If not a boot disk, it probably only had the c partition.

Maybe, if you have lucky enough, the default partition table was not modified and you may try "salvage" to recover the data. Or maybe, it has the same label like other system buyed in the same date with the same model.
Por que hacerlo dificil si es posible hacerlo facil? - Why do it the hard way, when you can do it the easy way?
John Welsh_2
Regular Advisor

Re: Lost system disk label !!

Hi again,
Sorry for the delay in updating this.

After a lot of research and reverse
engineering I have successfully "rebuilt"
the label on the disk using information
from within the disk itself. The only thing
I had to guess was the swap size as partition a and the swap is the"offset"
into the rest of the disk. I guessed the swap as being either 2 x physical memory or 3 x physical memory. It turned out to be 3x.Basically the partition size and the fset name are within blocks on the disk.

I moved the disk to a VMS system and used dump to examine each block of root to
establish where the size resided. It was easy from there. Once I had root and swap
the other partitions were found.

It would be nice if there is a utility on
Tru64 to dump and /or search the data in each block. Anyknow of one ?