how can I find the default gateway of an ubuntu box
Solution 1:
Classic answer
route
Look for a line that says something like:
default 10.63.3.254 0.0.0.0 UG 0 0 0 eth0
The second column contains the default gateway, and the last column is the interface.
You can also use the ip command:
ip route
which will give you something like
default via 10.63.3.254 dev eth0
Solution 2:
You can also use "netstat -nr" (I usually leave the n in the flags, so as to not have to wait for host resolution if there's a DNS issue).