*BSD News Article 85863


Return to BSD News archive

Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!munnari.OZ.AU!news.ecn.uoknor.edu!news.wildstar.net!newsfeed.direct.ca!op.net!news.mathworks.com!fu-berlin.de!irz401!orion.sax.de!uriah.heep!news
From: j@uriah.heep.sax.de (J Wunsch)
Newsgroups: comp.unix.bsd.freebsd.misc
Subject: Re: Seeking advice on new system purchase
Date: 30 Dec 1996 21:55:26 GMT
Organization: Private BSD site, Dresden
Lines: 31
Message-ID: <5a9doe$huj@uriah.heep.sax.de>
References: <59dhb9$p6g@shellx.best.com> <59r9ka$m4f@csugrad.cs.vt.edu>
  <5a3vmj$59d@symiserver2.symantec.com>
Reply-To: joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch)
NNTP-Posting-Host: localhost.heep.sax.de
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8bit
X-Newsreader: knews 0.9.6
X-Phone: +49-351-2012 669
X-PGP-Fingerprint: DC 47 E6 E4 FF A6 E9 8F  93 21 E0 7D F9 12 D6 4E
Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:33329

tedm@agora.rdrop.com wrote:

> If the tape is a SCSI-1 that does not support/properly implement the
> SCSI disconnection command, (many older 4mm drives are like this, as
> well as most QIC's) then the tape will seize the SCSI bus while it
  ^^^^^^^^^^^^^^^^^^
> is doing it's thing.

Even the ``legendary'' types like the Archive Viper 150 did this,
there's no need to put them on a separate bus.

All modern QIC streamers (with `modern' probably referring to
everything younger than ~ 3 years) do it.

> Also, if the tape drive is external and separate, it can be turned
> off and unplugged and carried to another machine, used, and returned
> without powering down the Unix box.

You can also do this on your `live' SCSI bus. :) It's a matter of your
preference whether you can accept the risk.  I know quite a lot of
people (including myself :) who consider SCSI to be hot-pluggable.  Of
course, during a short period of time, the bus is not terminated then,
but if your drivers are well-written, the worst that happens is that
some bus transactions have to be repeated.

-- 
cheers, J"org

joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)