solution such as dial backup. Static routes were discussed earlier in the chapter and are probably
a well-known topic at this point.
By default, static routes are the most preferred routes because an administrator defines them.
This concept of one route being more preferred than another is known as administrative
distance. Depending on how it was derived, a particular route (whether static or dynamic) can
be more believable than another route derived by a less sophisticated method.
interface, or 1 if a next-hop address is defined. This makes them highly believable routes. It is
possible to alter administrative distance to make a route less preferred than routes that are
dynamically derived.
preferred the route. When the administrative distance of a static route is altered to the point
where it is less preferred than the dynamic routes derived by a dynamic routing protocol, it
becomes a "floating" static route. Example 6-26 illustrates configuring a floating static route.
distance of 200. If the dynamic routing protocol being used is RIP (default administrative
distance = 120), the static route is now less preferred than the dynamic route. Should the RIP
route be lost for some reason, the static route becomes the preferred route until the RIP route
returns. Table 6-3 displays the administrative distances of common routing protocols.