[1372] in linux-net channel archive
Linux PPP weirdosity...
daemon@ATHENA.MIT.EDU (Dekhyr Dragon)
Wed Nov 15 00:05:54 1995
Date: Tue, 14 Nov 1995 16:53:03 -0500 (EST)
From: Dekhyr Dragon <xdraco@panix.com>
To: linux-net@vger.rutgers.edu
Got a weird problem here. I'm using kernel 1.3.40 and ppp2.2.0c.
My setup: Bunch of modems hanging off a terminal server. An incoming
call will generate a telnet session which telnets into the Linux
machine. A caller sees what would be seen on an ordinary telnet. The
user's login shell will first determine if they want PPP; if so, start a
pppd.
The pppd line:
exec /sbin/pppd -detach silent local
Now, I can successfully dial in using another Linux box and set up PPP.
However, when I dial in using Windows (Trumpet) PPP, I get a very strange
occurance. According to kernel debug, Linux swears it is sending out
this packet:
80 21 01 01 00 0A 03 06 6F 70 71 74
However, Trumpet swears it is receiving this packet:
80 21 01 01 00 0A 00 03 06 6F 70 71 74
^^^^^
Needless to say, the FCS checksum fails, and the PPP connection will not
configure (this is an IPCP configuration packet). I'd try setting up a
transmit asyncmap on the Linux side, but I don't know how to do that. I
can't find any configuration option in Trumpet which will let me set the
receive asyncmap -- it defaults to 0.
The problem is, when I try to debug this by setting kernel debug on the
PPP client on Linux, either nothing comes out on the kernel debug file,
or I get a little bit of garbage. Oddly enough, kernel debug works
perfectly when I set it on the PPP server!
Now, the worst part about all this is that when I take Trumpet PPP and
use it to connect to an ISP here, the ISP sends:
80 21 02 24 00 0A 03 06 CC B3 5C 48
And the Trumpet PPP receives it OK! No bogus inserted bytes!
And, when I connect using the Linux PPP to the ISP, it works OK as well!
So, does anyone know what's going on here? (Yes, I've cross-posted to
linux-ppp).
Thanks,
--Dekhyr
