Lab 104 - BGP Filtering using Standard ACL - Learn Cisco

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Lab 104 - BGP Filtering using Standard ACL

Prerequisites: CCNP level skills.

Topology

Personal Note!
Back home! Resuming my bgp command study and posts. My company seem to have planned a lot of travels for me (well, beggars can't be choosers). These kind of study distractions I equate to a tcp slow start: they're inevitable impediments and must be factored in during study.
Solution: increase the dose of tenacity ;)

Pic. 1 - Topology Diagram.
Icons designed by: Andrzej Szoblik - http://www.newo.pl

Task 1
On R5 filter out all prefixes with even numbers on the third octet.
 
Solution

Task 1
On R5 filter out all prefixes with even numbers on the third octet.

Pic. 2 - Current BGP Table on R5.

R5 Configuration:
!
access-list 1 permit 0.0.0.0 255.255.254.255
!
route-map FILTER_EVEN deny 10
 match ip address 1
!
route-map FILTER_EVEN permit 999
!
router bgp 50
 no synchronization
 bgp router-id 172.16.105.5
 bgp log-neighbor-changes
 network 172.16.105.0 mask 255.255.255.0
 neighbor 10.1.35.3 remote-as 30
 neighbor 10.1.35.3 route-map FILTER_EVEN in
 no auto-summary
!

Verification:
Pic. 3 - BGP Table on R5.

Notice!
172.16.102.0/24, 172.16.104.0/24 and 172.16.144.0/24 are no longer in the BGP table on R5. The 'clear ip bgp * in' is required for this filter to take effect.

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