Re: ppp connected, but no IP, DNS, GW

From: Clifford Kite (
Date: 04/10/04

Date: Sat, 10 Apr 2004 13:43:25 -0500

OtisUsenet <> wrote:

> I've got RedHat 9 (2.4.20-8 kernel) on a ThinkPad T40.
> I am trying to get the modem to work. It is a Wintel modem (Agere),
> but Agere and/or IBM provide the driver for it, which I have
> installed.

Hmmm. A winmodem. Good luck!

> The machine identifies the modem and is able to connect to my ISP,
> start pppd, but the connection is only half-made - no DHCP information

DHCP is not involved in normal PPP usage, be it a regular landline PPP
connection or a PPPoE connection.

> is set:
> - no IP
> - no Gateway
> - no name servers

> `route -n` and `ifconfig` show only 'lo' interface.

Then the PPP link was never established.

> How do I get my IP, name servers, and the gateway to get set?

We need more information to find why the PPP link wasn't established
and provide answers.

> I have dialed up using these methods:
> - ifup ppp0
> - wvdialer <my setting name here>
> - redhat-config-network (by trying to activate the ppp0 device from
> there)

> Any help would be veeery muuuuch appreciated!
> Thank you.

1) Generate a detailed pppd/<chat or dialing frontend> log file:

     echo 'daemon.*;local2.* /var/log/ppp.log' >> /etc/syslog.conf
     killall -HUP syslogd
     echo debug >> /etc/ppp/options

     Run whatever (script, kppp, wvdial, ect.) to start pppd and/or chat.
     Configure chat with the -v option for the script. Configure a pppd
     dialing frontend (kppp, wvdial, ect.) for maximum verbosity and hope
     the messages are sent to ppp.log .

2) Post an exact copy of the messages in ppp.log (not hand-copied).

3) Clean up when done:

     rm /var/log/ppp.log
     sed '$d' /etc/syslog.conf > foo; mv foo /etc/syslog.conf
     killall -HUP syslogd
     sed '$d' /etc/ppp/options > foo; mv foo /etc/ppp/options

     Remove the chat "-v", or reconfigure the dialing frontend, to stop
     verbose logging (which may be sent to other system log files).

Note: All the changes to /etc/syslog.conf and /etc/ppp/options could
also be done by simply using an editor rather than the echo, sed, and
mv utilities. Making file changes by first creating foo as shown above
assumes that root's umask is 022.

Clifford Kite                Email: "echo xvgr_yvahk-ccc@ri1.arg|rot13"
PPP-Q&A links, downloads:            
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