[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: ppp mystery




On  21 Nov, this message from Bruce McIntyre echoed through cyberspace:
>> > ppp0      Link encap:Point-to-Point Protocol  
>> >           inet addr:210.50.216.137  P-t-P:192.168.84.41  Mask:255.255.255.255
>> >           UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
>> >           RX packets:3286 errors:1 dropped:0 overruns:0 frame:0
>> >           TX packets:2821 errors:0 dropped:0 overruns:0 carrier:0
>> >           collisions:0 txqueuelen:10 
>> >           RX bytes:2620221 (2.4 Mb)  TX bytes:182797 (178.5 Kb)
>> > 
>> > ppp1      Link encap:Point-to-Point Protocol  
>> >           inet addr:210.50.32.108  P-t-P:192.168.84.9  Mask:255.255.255.255
>> >           UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
>> >           RX packets:52 errors:0 dropped:0 overruns:0 frame:0
>> >           TX packets:51 errors:0 dropped:0 overruns:0 carrier:0
>> >           collisions:0 txqueuelen:10 
>> >           RX bytes:2043 (1.9 Kb)  TX bytes:1942 (1.8 Kb)
>> 
>> Why are there two PPP interfaces?
> 
> Good question. At the moment (with a working connection) there aren't.
> perhaps this is getting close to my problem... see attached files for the
> current situation.

Maybe because you have a broken setup and your connection went down,
prompting you to reopen a new connection (which was connection no. 2,
since pppd kept the first one up?). Would be strange, since I have
problems figuring that pppd wouldn't know the link died.... Also, serial
port locking should have prevented this.

>> > Kernel IP routing table
>> > Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
>> > 192.168.84.41   0.0.0.0         255.255.255.255 UH        0 0          0 ppp0
>> > 192.168.84.9    0.0.0.0         255.255.255.255 UH        0 0          0 ppp1
>> > 0.0.0.0         192.168.84.41   0.0.0.0         UG        0 0          0 ppp0
>> > ----
> 
>> But you can reach the other one. Making that the default gateway might
>> work. But the question is really where the other one comes from.
> 
> I think you are on the money there: I only have one modem and no ethernet...

The fact that above, ppp0 has the default route, and is non-operational,
makes me think it is an old, died connection. Why pppd didn't detect
link failure is another matter... Later, you reopened a link, which
didn't add a default route since pppd by default doesn't replace an
existing default route.

So, you ended up with the default route to a broken link, and the
working link not getting traffic.

Regarding link detection failure: is your pppd configured to do LCP
keepalives (see man page)? What type of modem cable, and what modem are
you using? Are you sure modem signals (DCD, DTR, DSR) are connected
between modem and computer? If the answer is no to both, pppd has no way
of detecting a link failure.

Cheers

Michel

-------------------------------------------------------------------------
Michel Lanners                 |  " Read Philosophy.  Study Art.
23, Rue Paul Henkes            |    Ask Questions.  Make Mistakes.
L-1710 Luxembourg              |
email   mlan@cpu.lu            |
http://www.cpu.lu/~mlan        |                     Learn Always. "



Reply to: