Are there any way to detect if the NIC is currently working ? On SUN station, they send loopback packets to detect, does the Linux/3c59x has similar methord? I used Linux as a firewall in my company, and sometimes( about 1or2 for 2 months) the 3c906B stop working and print error messages, or the HUB line disconnected by someone else. I want linux to detect and alert me if it can't forwarding pkts!!