Usage Scenario
On large-scale RIP networks, storing routing entries consumes a large number of memory resources, and transmitting and processing routes consume lots of network resources. RIP-2 classful summarization can address this problem. Route summarization allows multiple routes with the same IP prefix and destination IP address to be summarized into one, which reduces the number of routing entries and improves scalability and efficiency of large-scale networks.
If poison reverse has been enabled using the
rip poison-reverse command or split horizon has been enabled using the
rip split-horizon command, the default classful summarization function does not take effect. In this situation, run the
summary always command to re-enable this function.
Prerequisites
A RIP process has been created and the RIP view has been displayed using the rip command.
Precautions
Classful summarization does not take effect in RIP-1.
Route summarization configured on an interface takes precedence over that configured in the RIP process. The
rip summary-address command takes precedence over the
summary command.