[ixp1200] Connectivity questions

[Magesh Kannan]

Hi,

This is a question for the guys at Princeton. Can you please briefly
describe your hardware setup? I mean 

1. what cable (cross-over/straight-thru) you use to connect the ethernet
ports on the IXP1200 to the outside world.
2. if you always use a switch/hub between a host and the ixp1200 ethernet
ports.
3. what ethernet card and driver do you use on the machines that you
connect to the IXP1200 for the IPmm experiment.
4. if you force the speed on any of these ports to 10 Mbps etc.

Contrary to some advice on this list for my question on cabling, it seems
that the ethernet ports on the IXP1200 behave like ports on hubs. This
means that straight-thru cables have to be used to connect an IXP1200 port
to a PC's ethernet card. When I do this, the yellow LED on the IXP1200
port blinks and the LED in the LED bank in the middle of the two quad
connectors does not come on.

If I force the speed on the linux PC's interface to 10 Mbps (using
mii-diag), the link LED (in the LED bank) comes on, but when I try to send
traffic, there is some debug output on the IXP1200's serial port
(indicating packet reception) initially. After some time, there is no
further output and I get carrier errors on the PC (found from ifconfig).

The only configuration in which I have been able to make the IXP1200 ports
receive packets is this

 Linux PC's eth1 <--- STRAIGHT-THRU ----> 10 Mbps ONLY HUB 
	<----- CROSS-OVER ----> 1XP1200 ETH port

Consequently, I am confused.

Thanks,
Magesh