I just bought a Soekris 4801-50 for use with m0n0wall, and setup of 1.22
went smoothly. With a Comcast cable modem plugged into the WAN port and my
powerbook plugged into the LAN port, everything's copacetic. 

However, when I plug the Soekris and the laptop into a five-port Linksys
switch, the link lights on the Soekris come on, but the laptop can't get a
DHCP address. When also connected, neither does my desktop machine, also
running OS X 10.4.6. Both computers self-assign 169.* addresses, and can
ping enough other through the switch.

To test pinging the Soekris through the switch, I connected the laptop to
the LAN port, manually assigned an address, and verified that I had an
internet connection and could ping the Soekris until cows came home. Then
I connected the LAN port and the laptop to the switch. Link lights on the
LAN port (and the switch) came on, but I had no connectivity from the
laptop, and I could no longer ping the Soekris.

This seemed to point to the switch, which I swapped out for a similar
five-port Linksys hub, and got identical results. The hub has previously
and since been in active use with an old Airport base station acting as
the router, so I don't think it's the issue. 

I've cycled through six ethernet cables (five straight and one crossover),
all of which are fine when connecting the LAN port and the laptop
directly, and none of which behave as described above when connected to
the switch, the only difference being the expected crossover requirement
to run into the switch's uplink port.

I found a similar-looking problem in the archives, which went unresolved:

  http://www.m0n0.ch/wall/list/showmsg.php?id=122/55

I realize that this looks just like pilot error, and I'm cognizant that I
have been known to make errors, but my inability to ping the Soekris using
a manual IP assignment and with the LAN port's link lights blazing makes
me think I've covered my bases. 

Any suggestions welcome.

Thanks,

  -nat