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Route-map and unsuppress-map confusion

Requirment

In order to facilitate in keeping the global BGP tables as small as possible, your BGP routing policy dictates the Rouer5 should advertise one route representing your entire major network 132.1.0.0 to RB.

Since the Ethernet segment between R5 and RB in AS 264’s only connection to your network, AS 264 does not need to have any longer matches than the summary route.

In order to assure optimal forwarding throughout your internal, insure that no other routers see this summary route,

Do not apply any access-list or prefix-list filtering towards AS 264.

Note: That R5 connect to R13 via Frame Relay then to rest of the network, and to R4 via ISDN and to the rest of the network

R5:

router bgp 300

aggregate-address 132.1.0.0 255.255.0.0 summary-only

neighbor 132.1.35.3 route-map ANY_OTHER out

neighbor 132.1.35.3 unsuppress-map THE_RESET

neighbor 132.1.45.4 route-map ANY_OTHER out

neighbor 132.1.45.4 unsuppress-map THE_RESET

!

ip prefix-list DENY_ANY_OTHER seq 5 permit 132.1.0.0/16

!

route-map ANY_OTHER deny 20

match ip address prefix-list ANY_OTHER

!

route-map ANY_OTHER permit 30

!

route-map THE_RESET permit 10

I get confused between "permit" keyword in prefix-list command and "deny" keyword in route-map statement, I feel there is contradiction

1 REPLY
Silver

Re: Route-map and unsuppress-map confusion

Route map has such a characteristic.

ip prefix-list DENY_ANY_OTHER seq 5 permit 132.1.0.0/16

!

route-map ANY_OTHER deny 20

match ip address prefix-list ANY_OTHER

In the above config, route map does the following:

1.it checks the prefix - list ANY-OTHER .

2.prefix list says that 132.1.0.0/16 is the address to be checked by the route map.

3.route map statement says to DENY the ip address matched by the prefix list ANY_OTHER .In short, this address 132.1.0.0/16 is Denied.This config is correct.

In short,prefix-list aplplied to route-map is denied

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