So you are not sure are connected and iither your router or ethernet card are not working.

sudo tcpdump -i eth0 -n port 67 and 68
You don't need this command often and there are other ways to test output but if you want to be sure if your router and ethernet card are working this is one way.
Sample Output 
12:30:25.973064 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 00:24:2b:60:33:8d, length 302
12:30:25.979560 IP 192.168.1.1.67 > 255.255.255.255.68: BOOTP/DHCP, Reply, length 303
12:30:48.928099 IP 192.168.1.131.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 00:24:2b:60:33:8d, length 300

0
By: wsv123456
2010-08-18 19:36:06
sudo tcpdump
2
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What Others Think

nice, +1 for you For all newbies (like me) out there, please note you should request a new IP to a DHCP server, with either dhclient or dhcpd or whatever equivalent.
vlan7 · 804 weeks and 6 days ago
That's IF you're using dynamically-assigned IPs...some people prefer static IP assignment (including newbs).
unixmonkey11373 · 804 weeks and 6 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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