Reject log message; bgp_community comparaison

[Mikhail A. Grishin]

Arnaud Fenioux wrote, 28.01.2015 17:20:
> Hello the bird community,
>
> I’ve two small questions, I've put them in the same mail even if they are not related :
>
> 1/ I currently use this code in my config to reject “martians”
>
>          if ( is_martian() ) then {
>                  reject "prefix rejected by is_martian";
>          }
>
> Which prints in logs : <INFO> prefix rejected by is_martian
> Do you know if there is a way to add some variables in the log (like bgp_path.first, from or net) ?
>
>
> 2/ I’ve notice a “strange” behaviour when comparing communities, is this voluntary?

Hi,

<Ondrej Zajicek wrote to me some times ago>
--------
Match (~) is not a symmetric operator, its general syntax is
"instance ~ set/list/pattern", therefore pair ~ pair_set is OK,
also pair ~ pair_list (bgp_community) is OK. Matching pair_list against
pair_set is a generalization interpreted as
"For each pair X in pair_list try X ~ pair_set, return true if any X 
matches"
--------

Wbr,
Mikhail, MSK-IX


>
> Pair set have to be compared on the right :
> bird> show route where bgp_community ~ [ (51706,51706) ] count
> 2467 of 2467 routes for 2426 networks
>
> bird> show route where [ (51706,51706) ] ~ bgp_community count
> 0 of 2467 routes for 2426 networks
>
>
> Pair have to be compared on the left :
> bird> show route where (51706,51706) ~ bgp_community count
> 2467 of 2467 routes for 2426 networks
>
> bird> show route where bgp_community ~ (51706,51706) count
> 0 of 2467 routes for 2426 networks

>
>
> Thanks
>
> --
> Arnaud Fenioux
> Network Engineer - FranceIX
>


-- 
Best regards,
Mikhail A. Grishin <m.grishin at msk-ix.ru>