BIRD export reject not working

[Tim Weippert]

Hi, 

IIRC, bird added your local ASN before export filter, so 64515 is
neither first nor last in ASN Path, and it isn't exactly only 64515 in
the path.

I suggest to use something like:

if bgp_path ~ [= * 64515 * =] then reject;

This should reject any bgp_path contains AS 64515.

HTH, 
tim

On Tue, Sep 19, 2017 at 10:50:47AM +0200, Marek Królikowski wrote:
> Hello guys,
> I got strange problem with BGP i share data to Collector but i put to reject
> some bgp path....
> 
> This is how look configuration of BGP session of Collector:
> 
> protocol bgp Collector {
>    description "Collector";
>    local as MY-ASN;
>    source address IPv61;
>    neighbor IPV62 as SOMEONE-ASN;
>    multihop;
>    import none;
>    export filter {
>    if bgp_path.first = 64515 then reject;
>    if bgp_path = 64515 then reject;
>    if bgp_path.last = 64515 then reject;
>    include "export.conf";
> };
> }
> 
> But:
> root at pl-bgp:~# birdc6 show route export Collector all 2a0b:e206::/32
> BIRD 1.6.3 ready.
> 2a0b:e206::/32     via 2a06:1287:330e:16::2 on bgp-fr [France 2017-09-18] *
> (100) [AS21430i]
>        Type: BGP unicast univ
>        BGP.origin: IGP
>        BGP.as_path: MY-ASN 64515 20473 1299 21430
>        BGP.next_hop: 2a07:XXXX.XXXX.XXXX
>        BGP.local_pref: 100
>        BGP.community: (64515,44)
> 
> Like You see in BGP path there is 64515.
> How i export this to Collector if i put reject on export?
> What is wrong?
> 
> I use BIRD 1.6.3.
> 
> Best Regards
> Marek Krolikowski
> 
> 

-- 
Tim Weippert
http://weiti.org - weiti at weiti.org
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