The route
command is used to show/manipulate the IP routing table. It is primarily used to setup static routes to specific host or networks via an interface.
Display existing routes
# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 10.2.8.1 0.0.0.0 UG 0 0 0 eth0
10.2.8.0 * 255.255.252.0 U 0 0 0 eth0
10.10.16.0 10.10.32.53 255.255.240.0 UG 0 0 0 tun0
Change default gateway
# route del default
route add default gw 10.2.0.4
Add a route for a given network
route add -net 172.17.255.0/24 gw 195.54.62.1
Remove a route for a given network
route del -net 172.17.255.0/24 gw 195.54.62.1
Reject routing for a given network
route add -net 192.168.1.0/24 reject