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From: resnick@cogsci.uiuc.edu (Pete Resnick)
Newsgroups: comp.sys.mac.comm
Subject: Re: MacTCP problem?
Message-ID: <1990Dec4.102039.29260@ux1.cso.uiuc.edu>
Date: 4 Dec 90 10:20:39 GMT
References: <4890@husc6.harvard.edu> <703@nih-csl.nih.gov>
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Organization: University of Illinois at Urbana
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ken@helix.nih.gov (Ken Weeks) writes:

>My Mac is on the Ether directly, via a Cabletron card.

OK, now I have a guess, and this will probably work. Evidently some
Ethernet card makers don't deal properly with maximum segment size that
MacTCP tells it to have, though somehow the non-MacTCP version of NCSA
Telnet does not have this problem. (Of course, MacTCP does not use
config.tel to figure out the segment size, as one person thought, but
takes care of it itself). The behavior you describe is *exactly* the
behavior of my Dove SE card when I am connected to a local (no routers)
IBM RT, thought it does not happen on a Sun or an Ultrix machine, or
when I am going through a router. I would not be suprised if Cabletron
has the same problem.

Luckily, the answer is to use the same patch that was used to fix the
problem with Localtalk macs in MacTCP 1.0 with MacTCP 1.0.1. Steve
Dorner at UIUC wrote the patch. Using ResEdit or equivalent, go into
the MacTCP file and open the DRVR resource (in ResEdit 1.2, I think you
had to choose Open General... to get it open). Then do an "Open using
Hex editor" so that you can see the Hex code for the ".ipp" driver.
Find the string "337c02040014" and replace it with the string
"337c01010014".  Then save and close the file. Evidently, this just
tells MacTCP not to say anything about segment size, and that should do
it.

Good luck,
pr
--
Pete Resnick             (...so what is a mojo, and why would one be rising?)
Graduate assistant - Philosophy Department, Gregory Hall, UIUC
System manager - Cognitive Science Group, Beckman Institute, UIUC
Internet/ARPAnet/EDUnet  : resnick@cogsci.uiuc.edu
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