SCSI Tape Drive Problems

[Dan Nelson]

In the last episode (Dec 20), Mark Kane said:
> On Tue, Dec 19, 2006, at 23:16:45 -0600, Dan Nelson wrote:
> > Timeouts and unexpected busfree errors like these are indicative of
> > cabling or termination problems.  I don't think DLTs auto-terminate,
> > for example, so try putting an external terminator on the 2nd plug on
> > the back of the unit (or if it's an internal drive with one plug,
> > terminate the cable the drive's plugged into).  Once you get those
> > errors sorted out, see whether you still get incorrect volume full
> > messages.
> 
> Thanks very much for the replies. Both drives are external, and they
> both have terminators on the back. The setup is like this:
> 
> The DDS autoloader is connected to the back of the Adaptec card via a
> new external HD68 cable and the terminator that came with the drive
> is on the second plug of the unit.
> 
> The Sun DLT drive is connected via an external HD50 cable to an adaptor
> that turns it into an internal cable which is then connected to the
> Adaptec card internally. It has a Sun terminator on the second plug on
> the unit.
> 
> The cable that connects the DDS autoloader is brand new. It's not a
> major brand name, but it's listed as "double shielded", "UL20276
> listed", etc. The cable that connects the DLT unit is an older Adaptec
> one (possibly used) purchased for a few dollars locally. I could
> understand if that cable was a problem for writing using that drive, but
> having the issue on both drives like this with two separate cables just
> seems like it's something else.
> 
> By the way, the green LEDs on both terminators are illuminated so they
> should be working.

All that looks okay to me.  Try reposting your question to the
freebsd-scsi at freebsd.org list.
 
> With the DDS drive, it does not give any errors to /var/log/messages
> like the DLT drive does. cpio just quits with that "Internal
> overflow, aborting" error (which doesn't happen with the DLT). Do you
> guys know specifically what that message means? With the DLT drive,
> cpio actually gives the volume full errors but with the DDS it's only
> "Internal Overflow" and nothing else anywhere that I can see.
> Internet searches for the "Internal Overflow" message have not turned
> up much helpful information.

If you look at the source to cpio, you can see in copyout.c, that
message is printed if a sprintf'ed header is larger than cpio expected
it to be.  My guess is one of your files is over 10gb and the file size
overflowed its 11-digit field.

-- 
	Dan Nelson
	dnelson at allantgroup.com