ip summary-address eigrp as-number ip-address mask [admin-distance] [leak-map name]
Posted by Peter Kurdziel on December 22, 2008
ip summary-address eigrp
To configure a summary aggregate address for a specified interface, use the ip summary-address eigrp command in interface configuration mode. To disable a configuration, use the no form of this command.
ip summary-address eigrp as-number ip-address mask [admin-distance] [leak-map name]
no ip summary-address eigrp as-number ip-address mask
Syntax Description
Defaults
•
An administrative distance of 5 is applied to Enhanced Interior Gateway Routing Protocol (EIGRP) summary routes.
•EIGRP automatically summarizes to the network level, even for a single host route.
•No summary addresses are predefined.
•The default administrative distance metric for EIGRP is 90.
Command Modes
Interface configuration
Command History
Usage Guidelines
The ip summary-address eigrp command is used to configure interface-level address summarization. EIGRP summary routes are given an administrative distance value of 5. The administrative distance metric is used to advertise a summary without installing it in the routing table.
By default, EIGRP summarizes subnet routes to the network level. The no auto-summary command can be entered to configure subnet level summarization.
EIGRP Support for Leaking Routes
Configuring the leak-map keyword allows to advertise a component route that would otherwise be suppressed by the manual summary. Any component subset of the summary can be leaked. A route map and access list must be defined to source the leaked route.
The following is default behavior if an incomplete configuration is entered:
•If the leak-map keyword is configured to reference a nonexistent route map, the configuration of this keyword has no effect. The summary address is advertised but all component routes are suppressed.
•If the leak-map keyword is configured but the access-list does not exist or the route map does not reference the access list, the summary address and all component routes are sent.
Examples
The following example configures an administrative distance of 95 on interface Ethernet 0/0 for the 192.168.0.0/16 summary address:
Router(config)# router eigrp 1
Router(config-router)# no auto-summary
Router(config-router)# exit
Router(config)# interface Ethernet 0/0
Router(config-if)# ip summary-address eigrp 1 192.168.0.0 255.255.0.0 95
The following example configures the 10.1.1.0/24 subnet to be leaked through the 10.0.0.0 summary address:
Router(config)# router eigrp 1
Router(config-router)# exit
Router(config)# access-list 1 permit 10.1.1.0 0.0.0.255
Router(config)# route-map LEAK-10-1-1 permit 10
Router(config-route-map)# match ip address 1
Router(config-route-map)# exit
Router(config)# interface Serial 0/0
Router(config-if)# ip summary-address eigrp 1 10.0.0.0 255.0.0.0 leak-map LEAK-10-1-1
Router(config-if)# end
princeklites said
nice description of ip Summary address concept.. could have been a little better with more detail and topological effect..
regards
princeklites said
Nice description sir, could have been a little more helpful with a topology in use.
regards