Hi!
Trying to kill the keyboard, [EMAIL PROTECTED] produced:
> I am unable to get my HP C1599A SCSI DAT tape drive to work with Linux.
> Both KBackup and kdat (which I'd like to use) report verify errors.
Try the following:
Use an empty tape, the test will overwrite it!
Create a file of some MB size (not just from /dev/zero, use
a tar of something or a dd of the first few MBs of your HD).
You'll want enough space on your HD to keep the file twice!
Let us prepare the tapedrive. We'll switch compression off,
to eliminate another possible source of errors.
mtst setblk 0 # set blocksize to variable
mtst datcompression # let's see if hardware
# compression is on
mtst datcompression 0 # ... and switch it off
mtst rewind
Now, the first test. Basic operation.
cat FILE > /dev/TAPE
mtst rewind
cat /dev/TAPE > FILE.READ
cmp FILE FILE.READ && echo All is OK.
If that test fails, then the problem is probably a cable or
something like that or the unit is b0rken.
Let's see if we can read it through a buffer.
rm FILE.READ
mtst rewind
cat /dev/TAPE | buffer -S 100k -m 10M > FILE.READ
cmp FILE FILE.READ && echo All is OK.
If that test fails, you cannot use buffer for reading the
tape. That may be inconvenient but is not fatal. You'll
just have to tell your backup program ...
Now, let's see if *writing* through a buffer works.
rm FILE.READ
mtst rewind
cat FILE | buffer -S 100k -m 10M > /dev/TAPE
mtst rewind
cat /dev/TAPE > FILE.READ
cmp FILE FILE.READ && echo All is OK.
If that test fails, again. it's not fatal, but you'll better
do *not* use any buffering (at least via buffer) for the tape
drive. My tape drive (Vendor: HP Model: HP35480A Rev: T603,
according to /proc/scsi, a DAT-2) is unreliable with buffering
and will lose bytes all over the backup if I use buffer.
It works OK (though slowly[1] for still uninvestigated reasons)
without 'buffer'. Any tips here?
-Wolfgang
[1] 160-180KB/s with internal compression switched off or
incompressible data, 350KB/s with compression on on
compressible data. Thats 600 MB/h. Is that normal?
