Recipe continued

$ ping <gateway_IP> - Usually $ /sbin/route -n will tell you what your gateway is. If it fails, your cable is bad.
$ host www.cmu.edu – If this fails, your DNS resolution doesn't work. Check /etc/resolv.conf – it should have at least one nameserver's IP listed there, and you should be able to ping that IP.
$ ping www.cmu.edu – If this fails, your gateway is not routing your traffic to the Internet. Talk to your network administrator, your local configuration seems to be fine.

$ ping <gateway_IP> - Usually $ /sbin/route -n will tell you what your gateway is. If it fails, your cable is bad.