Re: AUTOMATIC INCOMING FILTERING

[Matthew Walster]

On 10 August 2017 at 16:27, Janvier Rwakagabo 
wrote:
>
> Has anyone automated prefix filtering, for example if a peer acquire a new
> prefix to be received automatically may be any IRR, you can share the
> working configuration.
>

​Janvier,

Yes, there are many ways of doing this. In the past, I've used things like
https://github.com/snar/bgpq3 and I've been playing around with my own
version too: https://github.com/dotwaffle/prefixlister​

Essentially, you run those tools periodically with the ASN or AS-SET you
want to generate the prefixes for, saving the output to a file. You then
include that file from within your main bird.conf and specify that prefix
set within your policy.

Be warned, though: While the RIPE region generally has very good IRR
listings (route/route6 objects) things aren't so good in other RIRs -- many
North American networks register at RADB, as do other regions if there
isn't a nice IRRDB available at their RIR, but especially in regions like
Asia and South America you will find a very low takeup of RPSL entries in
an IRRDB.

If you choose to peer with a network that does not have route objects
covering all of it's networks, you would do very well to at the very least
implement a prefix-limit on the BGP session, that stays "hard down" if it
is tripped.

Matthew Walster

AUTOMATIC INCOMING FILTERING

[Janvier Rwakagabo]

Hi All

Has anyone automated prefix filtering, for example if a peer acquire a new
prefix to be received automatically may be any IRR, you can share the
working configuration.

Find on the attachment the manual prefix list filtering I am using,  

Regards,

Janvier R.

filter bgp_in_AS
prefix set PL_in_;

{

if ! (avoid_martians()) then reject;

if (bgp_path.first !=  ) then reject;

PL_in_ = [ a.b.c.d {16,24}, c.d.f.d/24 ];

if net ~ PL_in_ then accept;

else reject;

}

# Protocol templates

template bgp PEERS{
local as ;
route limit 1000;
export all;
rs client;
}

protocol bgp Raha from PEERS{
 description "Peer-Raha";
 neighbor 196.223.B.C as ;
 import filter bgp_in_AS;
}