Configure IRMP Route Control

Configuration Condition

Before configuring the IRMP route control, first complete the following tasks:

• Configure the IP address of the interface to enable the neighboring nodes to be reachable at the network layer.
• Enable the IRMP protocol.

Configure IRMP Route Summary

Both the IRMP aggregated route and original detailed route exist in the local routing table, but only the aggregated routing is informed to the neighbor. Thus, in the large-size network, the neighboring routing table scale reduces and the network bandwidth consumed by the protocol packets also reduces.

The IRMP supports the automatic summary and interface IP address summary. The metric value of the aggregated route uses the minimum metric value of all the detailed routes.

1. Automatic summary

In this mode, the route is aggregated as the corresponding classful network address by the non-manual configuration. The automatic route mode only aggregates the directly connected network segment route.

Table 11-4 Configure the IRMP automatic summary

2. Interface route summary

The interface route summary needs the user to configure the combination of a pair of destination IP address and mask. This combination aggregates the routes that are covered in this network segment.

Table 11-5 Configure the IRMP interface route summary

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  The automatic summary only aggregates the directly connected network segment routes and nay cause all neighbors under the process to reestablish.
• The interface route summary aims at all the IRMP routes delivered from the specified interface and may cause neighbors on the specified interface to reestablish.
• The interface route summary priors to the automatic summary.
• The interface route summary is independent with each other. That is, when the interface route summary 10.1.0.0/16 and 10.0.0.0/8 are configured at the same time, the IRMP will advertise the two summary routes simultaneously.

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Configure IRMP Administrative Distance

The administrative distance performs the routing policy for the routing in the same network augment from different protocols. The smaller the administrative distance is, the higher the priority of the routing is. You can change the administrative distance of the IRMP routing to affect the routing policy.

Table 11-6 Configure the IRMP administrative distance

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  When configuring the IRMP administrative distance, all neighbors under the process may be reestablished.

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Configure IRMP Load Balancing

The IRMP supports the equal-cost load balancing and unequal-cost load balancing. When multiple routes with the same metric values to the destination network exist, equal-cost load balancing forms. When multiple routes with the different metric values to the destination network exist, you can run the variance command to change the conversion factor and form the unequal-cost load balancing.

Variance defines a conversion factor, which is used to determine the scope of the unequal-cost load balancing routing. When the metric value of a non-optimal routing is smaller than the metric value of the optimal routing multiplying the variance value, this routing is selected as the unequal-cost load balancing routing.

The maximum-paths command is used to control the maximum number of routings for IRMP load balancing, supporting a maximum of 6 paths for load balancing. When path-number is set to 1, the load function is cancelled. The number of paths for IRMP load balancing includes the number of equal-cost load balancing paths and unequal-cost load balancing paths. The path selected for IRMP load balancing depends on conversion factor variance.

Table 11-7 Configure the IRMP load balancing

Configure IRMP Route Filtering

Control the received or delivered routing through configuring the ACL or prefix list. The inbound and outbound routing filtering can be configured on the interface at the same time.

Table 11-8 Configure the IRMP route filtering

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  The IRMP routing filtering only supports the standard ACL.
• You can configure the filtering on all interfaces or use the interface-name parameter to specify the interface for configuring filtering. When the preceding two modes are configured at the same time, the configuration is valid when the preceding two filtering rules are set to permit.

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Configure IRMP Metric Offset

By default, the IRMP routing adopts the metric value advertised by the neighbor. In some application scenarios, the metric value requires modification. The user can rectify the metric value of a specified routing by configuring the IRMP metric offset.

If the inbound metric offset is configured, the routing metric value is modified, saved in the routing table, and then advertised to the neighbor upon receiving the IRMP routing. If the outbound metric offset is configured, only the metric value advertised to the neighboring routing will be modified and the local metric value remains unchanged.

Table 11-9 Configure the IRMP metric offset

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  The IRMP metric offset only supports the standard ACL.
• When configuring the IRMP metric offset, all neighbors under the process may be reestablished.

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Configure IRMP Route Metric Value

The IRMP calculates a composite metric value as the rout metric value based on the link features, such as link bandwidth, delay, load, and reliability. The calculation formula is as follows:

Route metric = 256 x ([k1 x (10 7 /Bandwidth) + k2 x (10 7 /Bandwidth)/(256 – Load) + k3 x (Delay/10)] x [k5/(Reliability + k4)])

Where, bandwidth is in the unit of kbit/s and delay is in the unit of microsecond. Each k value indicates the weighted value of the corresponding link feature. By default, the RMP uses the link bandwidth and delay as the metric value.

Table 11-10 Configure the IRMP route metric value