BGP communites filtering help

RouterOS Forwarding Protocols
1

Hi,

I need some help from BGP users.

I use a RB1000 for my BGP 3 peer connections:

  1. international
  2. national + peering
  3. local peering

The bgp2 peer bandwidth is overloaded and I need to filter some comunities(302,303,304) and announce routes (my routes?) to comunities 2209,2309,2409.

I didn’t used before and I’m not sure if it’s OK. Please help me.

I make a route filter for bgp-in-filter chain with bgp-connection=302 /303/304 action discard
Enable that bgp-in-filter filter in BGP2 peer at “in-filter” ?

But how I set to announce my routes to 2209 communities?

thanks

best regards
ronn

2

For announced networks you have to set up out-filter and use ser-bgp-community in routing filters.

3

sorry

out-filter and set-bgp-comunity and in action?
and this route filter enabled for the same bgp-peer?

I have a /21 IP class with an AS number xxx.
I need to annonce my routes for ex. to community 2209.

4

Set out-filter to peer which is advertising your prefix. Action typically is “accept”. And also custom communities are written in format x:x, so if you need to set 2209 then in routeros you must set 0:2209

Let’s say you set to bgp peer out-filter=peer1-out
Then filter should be:
/routing filter add chain=peer1-out action=accept prefix=x.x.x.x/y set-bgp-communities=0:2209