Problems with pppd -- Connection breaks after a little while

Problems with pppd -- Connection breaks after a little while

Post by Bob Ko » Thu, 31 May 2001 10:14:23



I just got an old IBM Thinkpad notebook (a 701C, with the
butterfly keyboard).  It's running Debian GNU/Linux 2.2 (potato) with a
2.2.19 kernel and has a powerful 19.2 kbps modem.  I'm trying to get ppp to
work on it; I'm using Debian's pppconfig to set it up.

I'm able to get the machine to connect to that dial-up system and maintain
an episodic connection; it's enough that I can some times briefly open a ssh
connection, but not enough that it's usable.  When a try pinging a machine I
get a few (around 8) pings with decent response times; then a whole bunch
with awful response times (~10000 ms), then a few good ones ones, then even
worse ones (~40000 ms), then a few good ones, and then the connection
becomes totally unusable.

I thought at first it might be a hardware problem, but using minicom I was
able to connect to the dial-up server and open a telnet connection using the
dial-up system directly.  Since I have no difficulty establishing a
long-lasting modem connection to the dial-up server, the problem must be
with pppd.  My /etc/ppp/peers/provider file looks like:

# This optionfile was generated by pppconfig 2.0.5.
#
#
hide-password
noauth
connect "/usr/sbin/chat -v -f /etc/chatscripts/provider"
debug
/dev/ttyS0
115200
defaultroute
noipdefault
user rekopp
remotename provider

and the chat script looks like:

# This chatfile was generated by pppconfig 2.0.5.
# Please do not delete any of the comments.  Pppconfig needs them.
#
# ispauth PAP
# abortstring
ABORT BUSY ABORT 'NO CARRIER' ABORT VOICE ABORT 'NO DIALTONE' ABORT \
 'NO DIAL TONE' ABORT 'NO ANSWER'
# modeminit
'' ATZ
# ispnumber
OK-AT-OK ATDT<phone number>
# ispconnect
CONNECT \d\c
# prelogin
# ispname
# isppassword
# postlogin
# end of pppconfig stuff

The pppd options file is the standard one for Debian.

Anybody have any ideas?

Thanks,
Bob
--

http://home.uchicago.edu/~rekopp

 
 
 

Problems with pppd -- Connection breaks after a little while

Post by Clifford Kit » Thu, 31 May 2001 11:42:55



> I just got an old IBM Thinkpad notebook (a 701C, with the butterfly
> keyboard).  It's running Debian GNU/Linux 2.2 (potato) with a 2.2.19
> kernel and has a powerful 19.2 kbps modem.  I'm trying to get ppp
> to work on it; I'm using Debian's pppconfig to set it up.

[...]

Quote:> # end of pppconfig stuff
> The pppd options file is the standard one for Debian.
> Anybody have any ideas?

Take pppconfig out and shoot it.

Try adding the pppd option crtscts and using the modem initialization
string ATZ&F.  Make sure that the modem does hardware flow-control.

If those suggestions don't do it for you then add the pppd debug and
chat -v options and post exact copies, not hand-copies, including
timestamps of the logged messages.

You might also take a look at

http://www.theory.physics.ubc.ca/ppp-linux.html

for other hints.

--


 
 
 

Problems with pppd -- Connection breaks after a little while

Post by Bob Ko » Thu, 31 May 2001 12:42:27




Quote:> Try adding the pppd option crtscts and using the modem initialization
> string ATZ&F.  Make sure that the modem does hardware flow-control.

D'oh.  Well, I feel like a moron...  Back in the day when I used modems
regularly, AT&F probably would have been one of the first things I would
have tried.  In any case, it fixed the problem.

Thanks,
Bob
--

http://home.uchicago.edu/~rekopp