[comp.sys.apollo] tar cartrige from SUN

bonnetf@apo.esiee.fr (bonnet-franck) (08/21/90)

Hello,

I just came back from holidays (BIARRITZ is a great place for surfing !)
and then the reality is back.

I have a cartrige generated by tar on a SUN (don't know the type) and 
it is REALLY impossible to read it with APOLLO's tar,maybe I'm wrong
somewhere but I don't know where. 

Has anyone an idea ?
Thanks.

-------------------------------------------------------------------------------|
bonnetf@apo.esiee.fr                     |                                     |
Frank Bonnet                             | Surfing ...                         |
E.S.I.E.E                                |                                     |
BP99 93162 Noisy le Grand cedex.FRANCE.  | the rest is details !               |
Fax   : 33 1 45 92 66 99                 |                                     |
-------------------------------------------------------------------------------|

krowitz@RICHTER.MIT.EDU (David Krowitz) (08/21/90)

Sun's tar cartridge tapes may or may not be physically readable on the
Apollo's tape drive. The Apollo drives (including the newer SCSI cartridge
tape drives) use the QIC-24 recording format, which puts 60 MB of data on
a DC600A cartridge or 45 MB onto a DC300XL/P cartridge. Older Sun-3's had
drives which could recording in both the older QIC-11 format and the QIC-24
format. The QIC-11 format is a lower density format which you got when you
used the /dev/rst0 device. When you used /dev/rst8, you got the QIC-24 format.
QIC-11 tapes are not readable on the Apollo drives.

If your tape came from a Sparcstation, the situation is different. The Sparc
cartridge tape drives use DC600 series tapes only (the DC300XL/P's won't work),
and can handle either the QIC-24 format or a newer, higher density format
(maybe QIC-120?) which puts 120 MB onto a DC600A cartridge. Again, the format
depends on the device used to write the tape. The Sparcstation tapes are
readable *if* they were written in QIC-24 format *and* you are using an
SR10 machine to run "tar" (in particular: our DN3500 with the internally mounted
SCSI cartridge tape drive running SR10.2 works fine with a simple
"/bin/tar xvf /dev/rmts8" -- we've used this before in the recent past. I
think our DN560 also worked with "/bin/tar xvf /dev/rct8").


 -- David Krowitz

krowitz@richter.mit.edu   (18.83.0.109)
krowitz%richter.mit.edu@eddie.mit.edu
krowitz%richter.mit.edu@mitvma.bitnet
(in order of decreasing preference)

joey@tessi.UUCP (Joe Pruett) (08/24/90)

There is a lot of confusion about tape formats, so now I'll add
to the confusion :-)

The newer sun systems can read/write QIC-150 onto DC-6150 tapes
which gives 150 megabytes, and they can read QIC-24 on any flavor
of DC tape (15-60 meg).

Most other suns can read/write QIC-24 and QIC-11 on any DC tape.
Both formats are the same density, but QIC-11 isn't as likely to
read on foreign systems because of alignment differences.

Extremely old sun-2 systems could only read/write QIC-11 and only
4 tracks (QIC-24 is 9 track).  Max capacity is around 20meg.

I've never had a problem switching tapes between suns and apollos
as long as i use QIC-24 format.  I've used DC-150 through DC-600
without any problems.