Configuring IP Routing in Our Network
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Static routing has the following benefits:
No overhead on the router CPU
No bandwidth usage between routers
Security (because the administrator only allows routing to certain
networks)
Static routing has the following disadvantages:
The administrator must really understand the internetwork and how
each router is connected to configure the routes correctly.
If one network is added to the internetwork, the administrator must
add a route to it on all routers.
It's not feasible in large networks because it would be a full-time job.
The command used to add a static route to a routing table is
ip route [destination_network] [mask] [next-hop_address
or exitinterface] [administrative_distance] [permanent]
The following list describes each command in the string:
Ip route The command used to create the static route.
Destination network The network you are placing in the routing table.
Mask The subnet mask being used on the network.
Next-hop address
The address of the next-hop router that will receive
the packet and forward it to the remote network. This is a router inter-
face that is on a directly connected network. You must be able to ping
the router interface before you add the route. If you type in the wrong
next-hop address, or the interface to that router is down, the static route
will show up in the configuration of the router, but not in the routing
table.
Exit interface Used in place of the next-hop address if desired. Must
be on a point-to-point link, such as a WAN. This command does not
work on a LAN, such as Ethernet.
Administrative distance By default, static routes have an administrative
distance of 1. You can change the default value by adding an administra-
tive weight at the end of the command. Administrative distance will be
discussed further in the dynamic routing section later in this chapter.
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