Formatting a tape?

[Warren Block]

On Thu, 19 Mar 2009, Jaime wrote:

> On Thu, Mar 19, 2009 at 1:39 PM, Andrew Hamilton-Wright <andrew at qemg.org> wrote:
>> What happens if you use dd to try and write to the tape?
>>
>> The command
>>        dd if=/dev/zero of=/dev/sa0 count=8
>> should print out:
>>        8+0 records in
>>        8+0 records out
>
> I tried this and the output was:
> 8+0 records in
> 8+0 records out
> 4096 bytes transferred in 0.036611 secs (111879 bytes/sec)

Small write works okay...

> So then I tried my backup script (which is basically a tar command)
> and got this on the console:
> (sa0:ahc0:0:6:0): Unexpected busfree in Data-out phase
> SEQADDR == 0x86
> (sa0:ahc0:0:6:0): lost device
> (sa0:ahc0:0:6:0): failed to write terminating filemark(s)
> (sa0:ahc0:0:6:0): tape is now frozen- use an OFFLINE, REWIND, or MTEOM
> command to clear this state.
> (sa0:ahc0:0:6:0): removing device entry

Bigger write fails...

> On the ssh terminal / standard output, I got this:
> tar: Write error: Input/output error
>
> Now "camcontrol devlist" doesn't show the tape drive, even though it
> did before.

And the device acts flaky.  That screams "SCSI termination problem" to 
me.  That would also be consistent with most/all of the tapes failing, 
because it's not the tapes.

...

> I'm going to tinker some more and see if I can get this drive working
> again.  I'll also try another tape.  (Its worth noting that I DID
> manage to get a tape working thanks to mt -f /dev/sa0 fsf 1 && mt -f
> /dev/sa0 rewind.)  More info later.

Try that one working tape again.  Betcha it "fails".

-Warren Block * Rapid City, South Dakota USA