Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!newstop!eastapps!bodleian!geoff
From: geoff@bodleian.East.Sun.COM (Geoff Arnold @ Sun BOS - R.H. coast near the top)
Newsgroups: comp.protocols.nfs
Subject: Re: NCSA telnet and PC-NFS
Message-ID: <6723@eastapps.East.Sun.COM>
Date: 13 Jun 91 15:00:53 GMT
References: <1991Jun12.102647.3385@fennel.cc.uwa.oz.au>
Sender: news@East.Sun.COM
Reply-To: geoff@east.sun.com (Geoff Arnold @ Sun BOS - R.H. coast near the top)
Organization: Sun Microsystems PC-NFS Engineering
Lines: 30

Quoth r_hockey@fennel.cc.uwa.oz.au (in <1991Jun12.102647.3385@fennel.cc.uwa.oz.au>):
#Can anyone explain this,
#I have beeb experimenting with NCSA telnet 2.3 on various machines on
#our PC-NFS network.  I find that where the PC has a 3com 3C501 card
#PC-NFS remains unaffected by using NCSA telnet, but PC's with a Western
#Digital WD8003E ethernet card PC-NFS crashes.  Is it the memory on the
#WD card that causes the problem?   If so can it be disabled?

In general, as has been restated many times on comp.protocols.nfs
and comp.protocols.tcp-ip.ibmpc, it is not possible to run
two TCP/IP stacks at the same time in the same system.

However.

In the case you describe, NCSA is trying to take over the network
interface, use it for a while, and then quit, allowing PC-NFS to
continue working. (Obviously you don't want to try accessing an NFS
drive while running NCSA!) Whether or not this works depends on the
statefulness of the board and the PC-NFS driver.  In the case of the
3C501, all NCSA has to do is restore the interrupt vector: there's
little or no state on the board. (There's actually not much of anything
on the board, but still....) However such a simple approach isn't
sufficient for the WD8003E. I suppose that if the WD803E driver had
been written more robustly, and had included recovery logic for such an
occurrence, then it could have been made to work. It wasn't. It
doesn't.)
--Geoff Arnold, PC-NFS architect(geoff@East.Sun.COM or geoff.arnold@Sun.COM)--
------------------------------------------------------------------------------
--       Sun Technology Enterprises : PC Networking group                   --
--   (officially from July 1, but effectively in place right now)           --