D-Link DGS-3630 Emulator 1 - Page 723

DGS-3630 Layer 3 Stackable Managed Switch CLI Reference Guide Example This example shows how to create an aggregate address. Switch# configure terminal Switch(config)# router isis Switch(config-router)# summary-address 10.1.0.0 255.255.0.0 Switch(config-router)# 51-45 summary-prefix This command is used to create aggregate prefixes for IS-IS. Use the no form of this command to remove the aggregation. summary-prefix IPV6NETWORK [level-1 | level-1-2 | level-2] no summary-prefix IPV6NETWORK Parameters IPV6NETWORK level-1 level-1-2 level-2 Specifies the summary prefix designated for a range of prefixes. (Optional) Specifies that only routes redistributed into level 1 are summarized with the configured prefix value. (Optional) Specifies that the summary routes are applied when redistributing routes into level 1 and level 2 IS-IS and when level 2 IS-IS advertises level 1 routes as reachable in its area. (Optional) Specifies that the routes learned by level 1 routing are summarized into the level 2 backbone with the configured prefix value. Redistributed routes into level-2 IS-IS will be summarized also. Default By default, no aggregation is configured. Command Mode IPv6 Address Family Configuration Mode. Command Default Level Level: 12. Usage Guideline Multiple groups of prefixes can be summarized for a given level. Routes learned from other routing protocols can also be summarized. The metric used to advertise the summary is the smallest metric of all the more specific routes. This command helps reduce the size of the routing table. This command also reduces the size of the LSPs and thus the LSDB. It also helps network stability because a summary advertisement is depending on many more specific routes. A single route flap does not cause the summary advertisement to flap in most cases. The drawback of summary prefixes is that other routes might have less information to calculate the most optimal routing table for all individual destinations. 718