Checking your gateway address

Your computer grabs an IP address from a router; this router is also referred to as the default gateway as it connects you to the outside world (internet). Those routers are everywhere; they are at your house, coffee shops, schools, hospitals, and so on.

You can check the IP address of your default gateway by running any of the following commands:

• route -n
• netstat -rn
• ip route

Let's start with the first command, route -n:

root@ubuntu-linux:~# route -n Kernel IP routing table
Destination Gateway       Genmask       Flags  Metric Ref Use Iface
0.0.0.0     172.16.1.254  0.0.0.0       UG     600     0   0 wlan0
172.16.1.0  0.0.0.0       255.255.255.0 U      600     0   0 wlan0

You can see from the output that my default gateway IP address is 172.16.1.254. Now let's try the second command, netstat -rn:

root@ubuntu-linux:~# netstat -rn 
Kernel IP routing table
Destination   Gateway      Genmask       Flags  MSS Window irtt Iface
0.0.0.0       172.16.1.254...