strange network lockup with em0

[Colin Faber]

Hi guys,

I don't know if this message belongs here or elsewhere. So about every 
15 to 18 days or so my em0 on amd64 7.3-STABLE machine just stops 
working. ifconfig indicates that em0 is still up, ip assigned, routing 
table good, just no traffic flows through that interface. Checking dmesg 
and system logs doesn't indicate anything wrong with the nic. I've 
experienced this issue with 7.2 forward.

Does anyone happen to have any suggestions on what I should look at next?

-cf