I've been backing up for several years to an Exabyte 8200 tape drive
on a SCSI interface. The usual sequence of operations is:
rewind tape
write tar of filesystem 1
write tar of filesystem 2
...etc...
rewind tape
compare tar of filesystem 1 with disk
compare tar of filesystem 2 with disk
...etc...
rewind tape and eject
It has always worked fine.
Recently, I have been attempting to do incremental backups, and to
write multiple incremental backups to the same tape. I can't seem to
get it to work. The problem seems to lie in the sequence of
operations needed to space over the previously existing tar's and then
start writing the new tar. I usually get messages in syslog like:
Mar 15 16:12:24 blob kernel: st0: Error with sense data: extra data not valid
Current error st09:00: sense key Illegal Request
Unfortunately, not only do I get messages, the tar isn't written
correctly to the tape, either.
I've tried various variations to space the tape forward, including "mt
fsf", reading the tar, and "mt eod" (which seems to run forward to
EOT, rather than to the double tapemark indicating the end of data).
At this point, I'm tempted to believe that there are serious bugs in
either Linux 2.0.34, or in the Exabyte drive.
Does anyone have any idea what I can do?
Thanks,
Dale
