[realtek] Re: problem with dual RTL8139 boards

John A Ogren John.A.Ogren@noaa.gov
Wed Jan 2 14:58:01 2002

 > I think I see the problem here ...
 > ipadress with netmask will make all adresses
 > 192.168.1.x accessible by the interface
 > ipadress with netmask will make all adresses
 > 192.168.0.x accessible with the interface (and NOT 192.168.1.x)
 > (nothing meant for 192.168.1.x will even be sent out on that
 > interface, so if you run
 > tcpdump, that will suggest the card doesn't work)


Thanks for the suggestion, but I don't think that's the problem.  I 
assigned the address just to keep the two cards on different 
subnets.  All my tests trying to reach the local network used the address, and I just changed the physical slot and 
eth0.vs.eth1 assignment for different tests.

In the meantime, I have done more tests and I think that I've identified 
the problem.  There are really two problems:

1. I have to configure the BIOS to use level-triggered interrupts on the 
PCI bus.

2. I have to make sure to load the kernel module for the eth0 interface 

If I use edge-triggered interrupts, or load the kernel module for the 
eth1 interface first, then I run into problems accessing the local 
network from one or both cards.  But if I follow these two steps, I can 
access the local net from either card, configured either as eth0 or eth1.

Whew!  That was a tricky one to track down.  But now I think I'm ready 
for the cable modem installer to show up.

Thanks again to you and Donald for your comments.