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From: krowitz@RICHTER.MIT.EDU (David Krowitz)
Newsgroups: comp.sys.apollo
Subject: Re:  Accessing tape cartridge on other node?
Message-ID: <9102121409.AA12794@richter.mit.edu>
Date: 12 Feb 91 14:09:31 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
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Unlike disk devices (ESDI and SCSI hard disks, floppies, and opticals),
tape devices can only be accessed from the machine to which they are
physically attached. In fact, this is true for all I/O devices *except*
disk devices. The reason for this situation is that Domain/OS automatically
provides low-level servers for network disk I/O (these are the "netreceive",
"netpaging", and "netrequest" processes which show up when you do a
"/bin/ps -aux" command), but not for any other devices. It would have been
nice if servers for these other devices had been implemented, but Apollo
got caught up in doing Just Like Real Unix (JLRU) and has never had the
time to do anything else. OSF/1 won't even have the low-level disk servers
(it *will* have network disk I/O! Don't get me wrong ... but AFS is a
high-level network disk I/O server like NFS -- ie. your system must already
be booted up and have its TCP/IP servers running *before* the network disk
I/O can be used). You must either "crp", "telnet", or "rlogin" to the machine
to which the tape is attached before you can access it. This is likely to
be the case for the forseable future.


 -- David Krowitz

krowitz@richter.mit.edu   (18.83.0.109)
krowitz%richter.mit.edu@eddie.mit.edu
krowitz%richter.mit.edu@mitvma.bitnet
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