Configuring RIP-2 Route Summarization
Context
A large RIP network must maintain large RIP routing tables, which occupy a lot of memory on devices. Transmitting and processing the routing information requires many network resources. Route summarization can reduce the routing table size and minimize impact of route flapping on network.
RIP supports automatic summarization and manual summarization. Manual summarization takes precedence over automatic summarization. To advertise all subnet routes, disable automatic route summarization of RIP-2.
By default, if split horizon or poison reverse has been configured, classful route summarization is invalid. When summarized routes are sent to the natural network border, split horizon or poison reverse must be disabled.
Procedure
- Configure automatic route summarization of RIP-2.
- (Optional)
Run the summary always command to enable automatic
route summarization. This command can enable automatic summarization
of RIP-2 no matter whether split horizon and poison reverse are enabled.
The summary command is used in the RIP view to enable classful network-based route summarization of RIP-2.
- (Optional)
Run the summary always command to enable automatic
route summarization. This command can enable automatic summarization
of RIP-2 no matter whether split horizon and poison reverse are enabled.
- Configure manual route summarization of RIP-2.
- On an Ethernet interface, run undo portswitch
The interface is switched to Layer 3 mode.
By default, an Ethernet interface works in Layer 2 mode.
The mode switching function takes effect when the interface only has attribute configurations (for example, shutdown and description configurations). Alternatively, if configuration information supported by both Layer 2 and Layer 3 interfaces exists (for example, mode lacp and lacp system-id configurations), no configuration that is not supported after the working mode of the interface is switched can exist. If unsupported configurations exist on the interface, delete the configurations first and then run the undo portswitch command.
If many Ethernet interfaces need to be switched to Layer 3 mode, run the undo portswitch batch interface-type { interface-number1 [ to interface-number2 ] } &<1-10> command in the system view to switch these interfaces to Layer 3 mode in batches.
- Run the rip summary-address ip-address mask [ avoid-feedback ] command to configure RIP-2 to advertise the local summarization
IP address.
The rip summary-address ip-address mask [ avoid-feedback ] command is run in the interface view to enable classless network-based route summarization of RIP-2.
- On an Ethernet interface, run undo portswitch