Static route operation

Static route operation 

6.1.2
This page will explain how static routes operate and how they are created.
Static route operations can be divided into these three parts:

• Network administrator configures the route
• Router installs the route in the routing table
• The static route is used to route packets.

An administrator must use the ip route command to manually configure a static route. The correct syntax for the ip route command is shown in Figure .
In Figures and , the network administrator of the Hoboken router needs to configure a static route to the 172.16.1.0/24 and 172.16.5.0/24 networks on the other routers. The administrator could enter either of two commands to accomplish this objective. The method in Figure specifies the outgoing interface. The method in Figure specifies the next-hop IP address of the adjacent router. Either of the commands will install a static route in the routing table of Hoboken.
The administrative distance is an optional parameter that indicates the reliability of a route. A lower value for the administrative distance indicates a more reliable route. A route with a lower administrative distance will be installed before a similar route with a higher administrative distance. The default administrative distance when using a static route is 1. In the routing table, it will show the static route with the outgoing interface option as being directly connected. This is sometimes confusing, since a true directly connected route has an administrative distance of 0. To verify the administrative distance of a particular route, use the show ip routeaddress command, where the ip address of the particular route is inserted for the address option. If an administrative distance other than the default is desired, a value between 0 and 255 is entered after the next-hop or outgoing interface as follows:

waycross(config)#ip route 172.16.3.0 255.255.255.0 172.16.4.1 130

If the router cannot reach the outgoing interface that is being used in a route, the route will not be installed in the routing table. This means if that interface is down, the route will not be placed in the routing table.
Sometimes static routes are used for backup purposes. A static route can be configured on a router that will only be used when the dynamically learned route has failed. To use a static route as a backup, set a higher administrative distance than the dynamic routing protocol.
The Lab Activities will show students how static routes are created and used to troubleshoot networks.
The next page will teach students how to configure static routes.