Configure RIP Route Control

Configuration Condition

Before configuring RIP route control, ensure that:

• Interface IP addresses have been configured so that neighbor nodes are reachable at the network layer.
• RIP is enabled.

Configure the Administrative Distance of RIP

One device can run multiple routing protocols at the same time. The device selects the optimal route from the routes that are learnt from different protocols based on the administrative distances. The smaller the administrative distance is, the higher the priority is.

Table 5-7 Configuring the Administrative Distance of RIP

Configure an RIP Route Summary

Through RIP route summary, a routing device summarizes subnet routes in a natural network segment to form a summary route. The summary route and the original subnet routes all exist in the RIP routing table.

After RIP route summary is configured, the device advertises only the route summary. This greatly decreases the size of adjacent RIP routing tables in a medium- and large-sized network and decreases the consumption of the network bandwidth by routing protocol packets.

A route summary takes the minimum value among metrics of all subnet routes as its metric.

RIPv1 supports automatic route summary mode, and RIPv2 supports the automatic route summary mode and the manual summary mode.

1. RIP auto route summary

Different from manual route summary, auto route summary enables RIP to automatically generate a natural mask route based on subnet routes in one natural network segment.

Table 5-8 Configure the Auto Route Summary Function

• ---

  RIPv1 does not support the route summary command.
• The tag of a route summary is 0, and minimum metric of the routes is taken as the route summary metric. If the auto route summary is configured, auto route summary has the priority.
• Exercise caution in using the auto route summary function. Ensure that it is necessary to perform auto route summary; otherwise, routing loops may be caused.
• When the auto route summary function of RIPv2 is enabled, if the interface of the advertised route and the route are in the same natural network segment, the update packet sent from the interface does not result in summary of all subnet routes in the natural network segment; otherwise, routes are gathered to form a natural network segment and then it is advertised.

  ---

2. Manual route summary

In manual route summary, a combination of a destination address and a mask need to be configured. The combination gathers all routes in the covered network segment for route summary.

Table 5-9 Configuring the Manual Route Summary Function

Configure the RIP Metric Offset

By default, RIP applies the route metric advertised by the neighbor device to the received routes. To modify the metric in some special application scenarios, you can configure the RIP metric offset to correct the metric of the specified route.

If the metric in the incoming direction is configured, RIP modifies the metric of the received routes and saves the routes into the routing table. When RIP advertises a metric to the neighbor devices, it advertises the new metric. If the metric in the outgoing direction is configured, the metric is modified only when RIP advertises a metric to the neighbor devices.

Table 5-10 Configuring the RIP Metric Offset

• ---

  Route metric offset supports only matching a standard access list.

  ---

Configure RIP Route Filtration

A router can filter the received or advertised routes by configuring an Access Control List (ACL) or prefix list. In receiving RIP routes, you can filter some learnt routes; or in announcing RIP routes, you can filter some routes that are advertised to neighbor devices.

Table 5-11 Configuring RIP Route Filtration

• ---

  In filtration based on ACL, only a standard ACL is supported.

  ---

Configure the Metric of the RIP Interface

If an interface is overwritten by an RIP process, the corresponding direct route is generated in the database, with the default metric 1. When the route is in the RIP database or it is advertised to neighbor devices, if the interface is configured with a metric, the interface metric is used as the metric of the route.

If the interface metric is changed, the RIP database immediately updates the corresponding direct route of RIP and advertises the new metric to the neighbor devices.

Table 5-12 Configuring the Metric of the RIP Interface

• ---

  Configuring the RIP interface metric affects only the metric of the direct subnet of the interface while it does not affect the metric learned by routes.

  ---

Configure the Routing Flag for an RIP Interface

The network administrator can attach tags to some routes. Then, in applying a routing policy, the network administrator can perform route filtration or route property advertisement based on the tags.

Only the routing tags of RIPv2 are supported.

Table 5-13 Configuring the Routing Flag for an RIP Interface

Configure the Maximum Number of RIP Load Balancing Entries

This command helps you to control the number of RIP load balancing entries for routing.

Table 5-14 Configuring the Maximum Number of RIP Load Balancing Entrie