Display default route
The following three commands display the current routing table:
# route
Output:
Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.1.0 * 255.255.255.0 U 0 0 0 ra0 default dsl-router 0.0.0.0 UG 0 0 0 ra0
# /sbin/route
Output:
Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 191.255.255.0 * 255.255.255.0 U 0 0 0 eth0 169.254.0.0 * 255.255.0.0 U 0 0 0 eth0 default 191.255.255.1 0.0.0.0 UG 0 0 0 eth0
You can use -n option, to display numerical addresses instead of trying to determine symbolic host names (via dns or /etc/hosts file). This is useful if you are trying to determine why the route to your nameserver has vanished.$
#/sbin/route -n
Output:
Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 191.255.255.0 0.0.0.0 255.255.255.0 U 0 0 0 venet0 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 venet0 0.0.0.0 191.255.255.1 0.0.0.0 UG 0 0 0 venet0
Please note that a destionation entry 0.0.0.0 (or default) is the default gatway. In above example 191.255.255.1 is a default gatway.
Add / setup a new route
The syntax is as follows:
route add default gw {IP-ADDRESS} {INTERFACE-NAME}
Where,
- IP-ADDRESS: Specify router IP address
- INTERFACE-NAME: Specify interface name such as eth0
For example if your router IP address is 192.168.1.254 type the following command as the root user:
# route add default gw 192.168.1.254 eth0
OR use hostname such as dsl-router:
# route add default gw dsl-router eth0
Setting route using GUI tools/command under Linux
If you find above command hard to use, consider using GUI tools. If your are using Red Hat/CentOS/Fedora core Linux type following command:
# redhat-config-network
OR
If you are using other Linux distribution use command:
# network-admin