Dell BigIron RX Series, Configuration Manual

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BigIron RX Series Configuration Guide 669
53-1002253-01
Chapter
24
Configuring RIP
Overview of Routing Information Protocol (RIP)
Routing Information Protocol (RIP) is an IP route exchange protocol that uses a distance vector (a
number representing distance) to measure the cost of a given route. The cost is a distance vector
because the cost often is equivalent to the number of router hops between the device and the
destination network.
A device can receive multiple paths to a destination. The software evaluates the paths, selects the
best path, and saves the path in the IP route table as the route to the destination. Typically, the best
path is the path with the fewest hops. A hop is another router through which packets must travel to
reach the destination. If the device receives a RIP update from another router that contains a path
with fewer hops than the path stored in the device’s route table, the device replaces the older route
with the newer one. The device then includes the new path in the updates it sends to other RIP
routers, including the device.
RIP routers, including the BigIron RX, also can modify a route’s cost, generally by adding to it, to
bias the selection of a route for a given destination. In this case, the actual number of router hops
may be the same, but the route has an administratively higher cost and is thus less likely to be
used than other, lower-cost routes.
A RIP route can have a maximum cost of 15. Any destination with a higher cost is considered
unreachable. Although limiting to larger networks, the low maximum hop count prevents endless
loops in the network.
Configuring RIP parameters
Use the following procedures to configure RIP parameters on a system-wide and individual
interface basis.
Enabling RIP
RIP is disabled by default. To enable RIP, you must enable it globally and also on individual
interfaces on which you want to advertise RIP. Globally enabling the protocol does not enable it on
individual interfaces. You can enable the protocol on physical interfaces as well as virtual routing
interfaces. When you enable RIP on a port, you also must specify the version (version 1 only,
version 2 only, or version 1 compatible with version 2).
To enable RIP globally, enter the following command.
BigIron RX(config)# router rip
Syntax: [no] router rip
After globally enabling the protocol, you must enable it on individual interfaces. To enable RIP on an
interface, enter commands such as the following.