From: CharlesB (cbalik@adelphia.net)
Date: Tue Sep 05 2006 - 13:02:01 ART
I think one of the requirement was to traffic direction management for the
vlan 5 on router R5 and advertising also an aggregate.
I assume this is the R4 router configuration you pasted here.
So, to be able to aggregate a block into BGP, at least one of the more
specific route belong to that aggregate address should be in the routing
table but should be in the BGP table.
So, Vlan 5 which is a RIP route or an IGP route in this case, should be in
R4's route table under BGP.
Here, we needed to take that route into BGP routing table to aggregate. They
are redistributing RIP but only taking Vlan 5 so that aggregate could work,
I assume. Then they are unsuppressing the same route out of aggregate so the
traffic direction management could work, because R4 will propogate aggregate
and more specific from one end of the AS, and the R6 on the end, will
propogate only aggregate, therefore the traffic will come to Vlan 5 throug
R4 which satisfies the goal.
http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a00800945ff
.shtml#topic5
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
tonynguyenchi
Sent: Tuesday, September 05, 2006 12:42 AM
To: ccielab@groupstudy.com
Subject: Fw: IEWB v3v1 lab 13 task 5.2 bgp distribute-list
Dear GS,
Why do we need to use distribute-list in BGP (following the solution)?
router bgp 100
bgp router-id 150.1.5.5
bgp log-neighbor-changes
neighbor 150.1.6.6 remote-as 100
neighbor 150.1.6.6 update-source Loopback0
neighbor 204.12.1.254 remote-as 54
!
address-family ipv4
redistribute rip route-map RIP_TO_BGP
neighbor 150.1.6.6 activate
neighbor 150.1.6.6 next-hop-self
neighbor 204.12.1.254 activate
neighbor 204.12.1.254 route-map ODD_ROUTES in
neighbor 204.12.1.254 unsuppress-map RIP_TO_BGP
distribute-list prefix DENY_AGGREGATE in
no auto-summary
synchronization
aggregate-address 139.1.0.0 255.255.0.0 summary-only
exit-address-family
!
ip prefix-list DENY_AGGREGATE seq 5 deny 139.1.0.0/16
ip prefix-list DENY_AGGREGATE seq 10 permit 0.0.0.0/0 le 32
Thanks and best regards,
Tony
This archive was generated by hypermail 2.1.4 : Sun Oct 01 2006 - 16:55:39 ART