BGP Outbound Route Filter (ORF) Capability


The BGP Outbound Route Filter (ORF) Capability allows for a routers to send their neighbor the prefix filter they are applying to inbound routes. The neighbor then applies this prefix-list to any routes they send to the neighbor. This helps save bandwidth and processing for something that would have be thrown away by the filter.

To Configure – Send Side

1) Create a Prefix-list with the routes to be filtered

R3(config)#ip prefix-list ORF deny 1.1.1.0/24 R3(config)#ip prefix-list ORF permit 0.0.0.0/0 le 32

2) Enable the capability to the neighbor and apply the prefix to the inbound routes from the neighbor.

R3(config)#router bgp 3 R3(config-router)#nei 10.1.23.2 capability orf prefix-list send R3(config-router)#nei 10.1.23.2 prefix-list ORF in

To Configure – Receive Side

1) Configure the capability to be received from the neighbor

R2(config-if)#router bgp 2 R2(config-router)#nei 10.1.23.3 capability orf prefix-list receive

Then execute

R3#clear ip bgp 10.1.23.2 in prefix-filter

to push the filter to the neighbor

The filter can be seen on the neighbor with “sh ip bgp neireceived prefix-filter”

R2(config-router)#do sh ip bgp nei 10.1.23.3 received prefix-filter
Address family: IPv4 Unicast
ip prefix-list 10.1.23.3: 2 entries
seq 5 deny 1.1.1.0/24
seq 10 permit 0.0.0.0/0 le 32

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About ccie4all
Hello, and welcome to the first post of my CCIE blog This blog has got one simple goal and that is to improve our skills in Cisco Networking field so we can become best engineers on a job market. Wordpress Blog https://ccie4all.wordpress.com/ information about the changes made to Gns3 BGP , MPLS and R&S CCIE labs. In order to access and download all provided materials and receive important updates from Gns3 BGP , MPLS and R&S CCIE labs under GNS3 tab in the main header please go ahead and subscribe to https://ccie4all.wordpress.com/ ! All other posts have not been affected and can be accessed at any given time. Enjoy ! Tom

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