Using a Sun tape drive under SunOS 4.1.1

[CStacy@STONY-BROOK.SCRC.Symbolics.COM (Christopher Stacy)]

I'd like to clear up some of the confusion about the UX tape access
problems that have been discussed recently here on SLUG.

The problem is that in SunOS 4.1.1, the Unix remote tape access interface,
a program called "rmt", seems to be broken.  Many rmt commands, notably
Rewind, F/B/Space, and Read Forward, case Unix to panic crash.  
(Those are just some of the operations I tried typing to rmt from a shell.)
This is bug in SunOS, and is not a problem with the Symbolics software.
However, Genera needs to access the tape drive, and this is how it's
supposed to be done under Unix.

Barry mentioned an RTAPE (our proprietary remote tape protocol) server
for Unix, but Symbolics does not have such a product.

Symbolics has duplicated the rmt bug and filed incident reports with SUN,
and they are working on it.  When they come up with a solution, we will
be able to advise our customers about which patch they should request
from SUN.  The last we heard, SUN's engineering department thought they
had a fix for the problem, but they had not yet generated and released a
patch to their support organization, and support was unable to give any
estimate of when a patch would be available. If you are experiencing this
problem, we recommend that you contact the software support organization
at SUN and try to get a patch from them.

So far, they actually gave us one patch which prevents the system from
crashing, but it doesn't make the tape drive work.  When you use rmt,
the patch makes Unix prints out on the console:
   "vmunix: st0: tape synchronization lost
    vmunix: psig: signal 15 was masked, put back"
and makes the rmt program get an error.  
I don't know anything about Unix, but that wording sounds to my ignorant
ears, something like, "tape device driver got screwed up; kernel's
interrupt handler state was bashed, decided to kludge it and abort".
Anyway, it certainly doesn't make the tape drive work.

We can't do much about this: it's a bug in Unix.  Call SUN.