1 Sep
2015
1 Sep
'15
3:12 p.m.
Yeah, your disk has got problems. Either an actual hardware problem or a
corrupted file system.
The FORCEDERROR flag usually means a hardware problem - bad disk block. It
means reading the disk, the checksum failed and retries did not successfully
read the data so the disk controller has flagged the block as bad. It looks
like this has happened in one of the blocks for the storage bitmap that VMS
uses in the interal file structure to maork used blocks. Doing an
ANALYZE /DISK /REPAIR dub0: may fix it. You also may have to initialize
the disk and run a bad block checker on it. Doing this will lose whatever
data is on the drive though so try the ANALYZE first.
ANALYZE /DISK /REPAIR dub0: requires the disk to be mounted first and the
forced errors on the bitmap likely won't allow that. It has a better chance of
working if the disk is backed up and restored onto a working disk, possibly an
emulated disk on simh or similar. ANALYZE /DISK /REPAIR is also a very blunt
weapon and when combined with media errors, it could mangle the disk much worse
so it's always a good idea to try it on a copy of the original.
Regards,
Peter Coghlan.