*BSD News Article 22229


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Path: sserve!newshost.anu.edu.au!dubhe.anu.edu.au!sirius!paulus
From: paulus@anu.edu.au (Paul Mackerras)
Newsgroups: comp.os.386bsd.questions
Subject: Re: modem hangup problem with PPP
Date: 11 Oct 1993 23:39:50 GMT
Organization: Computer Science Department, ANU, Australia
Lines: 48
Distribution: world
Message-ID: <29cqs6INNgpg@dubhe.anu.edu.au>
References: <29aed4$r0r@agate.berkeley.edu>
Reply-To: paulus@anu.edu.au
NNTP-Posting-Host: sirius.anu.edu.au

In article r0r@agate.berkeley.edu, stas@scam.Berkeley.EDU (Stan Malyshev) writes:
> 1.
> 
> '/usr/libexec/pppd /dev/sio01'  hangs up the modem immediately upon
> being run, and the following message gets echoed:
> 
> Oct  9 17:37:44 budo pppd[421]: Using interface ppp0
> Oct  9 17:37:44 budo pppd[421]: write
> Oct  9 17:37:44 budo pppd[421]: write
> 
> 
> I'd recompiled the kernel with 'pseudo-device   ppp', and  tip and SLIP
> seem to work allright.  What's wrong with PPP?
> 

Well, I assume that it's the pppd from the free ppp-1.2 or ppp-1.3 distribution
(the latter is what's distributed with FreeBSD).  That pppd drops DTR for one
second right at the beginning, then runs the `connect' script, if any, that
you have specified.  The intention is apparently to make sure that any existing
connection is terminated before it tries to make a new connection with the
connect script. I agree it's a pain, in the situation where you have already
established the connection.  What I usually do is to set the modem to ignore DTR.

> 2.
> 
> My SLIP (and PPP) gateway machine is non-local (phone-wise), and I am trying
> to first log into a local net provider, and then telnet to the gateway
> machine.  The SLIP session seems to get stuck (flow control?) right away,
> and nothing happens.  Binary zmodem transfers work from that machine, so
> I assume the link is 8-bit.  Doing 'stty -ixon -ixoff -opost cs8'
> didn't have any visible results.
> 
> Has anyone succeeded in SLIP-ing via a telnet/rlogin session (from a machine,
> not an annex port) ?

I found both telnet and rlogin to give problems.  With telnet, you have to
find some way to disable the escape character (normally ^]).  With rlogin,
you similarly have to disable the ~ escape and also make sure it's an 8-bit
path, and there is a further problem: rlogind on many machines watches for
the sequence 0xff 0xff 0x73 0x73 and removes those 4 bytes and the following
8, and interprets the 8 bytes as window size information.  That sequence
doesn't occur very often normally, but it infallibly occurs when you try to
do rlogin over [slip or ppp] over rlogin.

Paul Mackerras
Dept. of Computer Science
Australian National University.