05-04-2006 08:23 AM - edited 03-03-2019 12:36 PM
How do you configure BGP to filter out all routes except the default route that is being advertised by our ISP?
05-04-2006 08:46 AM
Try this link and check put the BGP route filtering section.
05-04-2006 09:31 AM
Hello,
you can apply an inbound filter based on a prefix-list. The config could look like this (adjust AS, IP addresses nd the like) assuming your official IPs are 1.1.0.0/16:
router bgp 65000
no synchronization
network 1.1.0.0 mask 255.255.0.0
neighbor 1.2.2.1 remote-as 1 !ISP BGP peer
neighbor 1.2.2.1 prefix-list OnlyDef in
neighbor 1.2.2.1 filter-list 1 out
no auto-summary
ip as-path access-list 1 permit ^$
ip prefix-list OnlyDef permit 0.0.0.0/0
ip route 1.1.0.0 255.255.0.0 Null 0 250
Hope this helps! Please rate all posts.
Regards, Martin
05-04-2006 08:17 PM
Hello Martin
I believe he's actually asking for the opposite:
"How do you configure BGP to filter out all routes except the default route that is being advertised by our ISP?"
He needs to filter out everything but the default route. (which I think its better to filter out, when you have more than 1 destination, not this case though)
I'd suggest to do the opposite.
Set
neighbor IP prefix-list def-out out
Besides, that your config looks neat.
vlad
Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: