Ethernet adapter problems

[Scott Holt]

We have a number of RS 6000s connected to our campus network -
a network which sees quite a bit of traffic. From time to time,
the ethernet interfaces in the machines will simply shut off.
One machine, a model 540, seems to have a particularly bad time
of it. It comes up just long enough for routed to learn a few
routes and then shuts off. Actually, it looks like the machine
receives just fine, but cannot send.

The following errors are logged with each attempted outbound packet:
	CMSA/CD LAN COMMUNICATIONS LOST
 and    COMMUNICATION PROTOCOL ERROR

The cabling checks out ok and the card passes diagnostics.

Any clues? Has anyone else had trouble with ethernet interfaces
shuting down under high traffic conditions. I might add, a significant
part of the traffic on our network is broadcast traffic generated
by various terminal servers.

- Scott