[plug] adsl trouble

[Craig Ringer]

> I have
> two network cards (eth0, eth1) in my box (setup as DHCP clients)
Both enabled and plugged in at the same time? this might confuse your 
router (it thinks they're 2 different machines unless it supports some 
kind of trunking or your switch (if not embedded in the router) does).

> and
> have tried using both, with the same result...the connection seems to
> come up fine when I boot, but after a couple of minutes it seems to die
> for no apparent reason.
Perhaps DHCP allocations change if its being confused by 2 NICs?
Can you still ping other machines on your LAN? Try using ifconfig -a to 
get the status on the interfaces too see if perhaps they're going down 
on dhcpcd/pump's request due to maybe a DHCP NACK from the router?

> I can easily get it back again using /sbin/ifup
> eth0 or 1, but after a few minutes or more the same thing happens again.
Have you tried "tail -f /var/log/syslog" or "tail -f /var/log/messages" 
and watching what the system is saying esp around the dropout time?

> If someone on the list
> could suggest a few things for me to check I would be very grateful, as
> running /sbin/ifup every 3 minutes is getting a little tedious :)

Not much info to go on unfortunately. Do the ifaces actually go down, or 
just stop sending packets? Can you still ping other machines on the LAN 
after connectivity to the internet is lost? Have you looked through the 
system logs for indications on what might be wrong?

Here's a best guess as to your network layout, including the assumption 
that the mandrake box is dual homed and both NICs are plugged in and 
configured (if so you might want to disable one though). Pls correct if 
needed.

           Gateway-------------------
           | |   |                  |
          |  |    |             windows2k
         |  |      |
        |   |        |
       |    |         |
      |      |          |
Mandrake-Mandrake    windowsXP
    eth0     eth1

Alternately might be
           Gateway
              |
           Switch-------------------
           | |   |                  |
          |  |    |             windows2k
         |  |      |
        |   |        |
       |    |         |
      |      |          |
Mandrake-Mandrake    windowsXP
    eth0     eth1