Modem/PPP trouble ...
Hello everyone,
I am having trouble setting up PPP for a friend's computer. Here
are the details:
486 running Debian 2.1; base system installed by floppies.
Modem: USR Sportster 33600 Internal ISA modem.
UART: 16450 (According to setserial)
Modem on /dev/ttyS1. No interrupt conflicts as far as setserial can see.
Speed setting for serial port - 19200. (I tried 9600 and got the same
problems).
I am using chat to connect to the university's dialup service. The IP
address is dynamically assigned.
The problems are:
1> With only hardware flow control (hfc) enabled, pon does not even dial
the number. (On an earlier Debian system on this computer, minicom did
require hfc "off" to work. But as far as I can remember, for the ppp
setting (which worked a few months back), I used the default
/etc/ppp/options - which enables hfc).
The chatscript usually aborts after sending ATZ to the modem. (Looks like
it keeps waiting for the OK from the modem and doesn't get it). On one
occasion, it did try to dial the number, and failed. The plog output:
chat[124]: send (ATZ^M)
chat[124]: expect (OK)
chat[124]: alarm
chat[124]: Failed
pppd[123]: Connect script failed
pppd[123]: Exit.
2> With sfc "on", the chatscript seems to work OK irrespective of hfc. It
does connect - but within a few minutes everything freezes up and the
connection is lost. (On some occasions, the link stayed up for about 2-3
minutes. For those few minutes - telnet worked, and I could ping other
machines).
The plog output on connecting:
chat[120]: 19200/ARQ/V34/LAPM/V42BIS^M
The user authentication works OK, and PPP connection is established ...
pppd[119]: Serial connection established.
pppd[119]: Using interface ppp0
pppd[119]: Connect: ppp0 <--> /dev/ttyS1
pppd[119]: sent [LCP ConfReq id=0x1 <asyncmap 0xa0000> <magic 0xb4ecdfe2> <pcomp> <accomp>]
pppd[119]: rcvd [LCP ConfReq id=0x3b <asyncmap 0xa0000> <magic 0x966cbc3e> <pcomp> <accomp>]
pppd[119]: sent [LCP ConfAck id=0x3b <asyncmap 0xa0000> <magic 0x966cbc3e> <pcomp> <accomp>]
pppd[119]: rcvd [LCP ConfAck id=0x1 <asyncmap 0xa0000> <magic 0xb4ecdfe2> <pcomp> <accomp>]
pppd[119]: sent [LCP EchoReq id=0x0 magic=0xb4ecdfe2]
pppd[119]: sent [IPCP ConfReq id=0x1 <addr 0.0.0.0> <compress VJ 0f 01>]
pppd[119]: rcvd [IPCP ConfReq id=0x6f <addr 136.152.192.35>]
pppd[119]: sent [IPCP ConfAck id=0x6f <addr 136.152.192.35>]
pppd[119]: rcvd [LCP EchoRep id=0x0 magic=0x966cbc3e]
pppd[119]: rcvd [IPCP ConfRej id=0x1 <compress VJ 0f 01>]
pppd[119]: sent [IPCP ConfReq id=0x2 <addr 0.0.0.0>]
pppd[119]: rcvd [IPCP ConfNak id=0x2 <addr 136.152.195.249>]
pppd[119]: sent [IPCP ConfReq id=0x3 <addr 136.152.195.249>]
pppd[119]: rcvd [IPCP ConfAck id=0x3 <addr 136.152.195.249>]
pppd[119]: Cannot determine ethernet address for proxy ARP
pppd[119]: local IP address 136.152.195.249
pppd[119]: remote IP address 136.152.192.35
pppd[119]: sent [LCP EchoReq id=0x2 magic=0xb4ecdfe2]
pppd[119]: rcvd [LCP EchoRep id=0x2 magic=0x966cbc3e]
pppd[119]: sent [LCP EchoReq id=0x3 magic=0xb4ecdfe2]
pppd[119]: rcvd [LCP EchoRep id=0x3 magic=0x966cbc3e]
pppd[119]: sent [LCP EchoReq id=0x4 magic=0xb4ecdfe2]
pppd[119]: sent [LCP EchoReq id=0x5 magic=0xb4ecdfe2]
pppd[119]: sent [LCP EchoReq id=0x6 magic=0xb4ecdfe2]
pppd[119]: rcvd [LCP EchoReq id=0x6 magic=0xb4ecdfe2]
pppd[119]: sent [LCP EchoRep id=0x6 magic=0xb4ecdfe2]
pppd[119]: rcvd [LCP EchoRep id=0x6 magic=0xb4ecdfe2]
pppd[119]: appear to have received our own echo-reply!
pppd[119]: sent [LCP EchoReq id=0x7 magic=0xb4ecdfe2]
pppd[119]: rcvd [LCP EchoReq id=0x7 magic=0xb4ecdfe2]
pppd[119]: sent [LCP EchoRep id=0x7 magic=0xb4ecdfe2]
pppd[119]: rcvd [LCP EchoRep id=0x7 magic=0xb4ecdfe2]
pppd[119]: appear to have received our own echo-reply!
pppd[119]: No response to 4 echo-requests
pppd[119]: Serial link appears to be disconnected.
pppd[119]: sent [LCP TermReq id=0x2 "Peer not responding"]
pppd[119]: rcvd [LCP TermReq id=0x2 "Peer not responding"]
pppd[119]: sent [LCP TermAck id=0x2]
pppd[119]: sent [LCP TermReq id=0x3 "Peer not responding"]
pppd[119]: rcvd [LCP TermReq id=0x3 "Peer not responding"]
pppd[119]: sent [LCP TermAck id=0x3]
pppd[119]: rcvd [LCP TermAck id=0x3]
pppd[119]: Connection terminated.
pppd[119]: Exit.
Any suggestions as to what is going wrong? Is this something to do with
the serial port speed - 16450 UART not being able to keep up with a 33.6
Kbps modem? Or should I have my modem connect to the dialup modem at a
lower speed? And why does enabling hfc without sfc make things go wrong?
Thanks --- Karthik
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