Hello Maria, hello Alexander, first of all, thank you very much for your suggestions.
On Tue, 26 Mar 2019, Maria Matějka wrote: > Did you try using BGP path mask? Like > if (bgp.path ~ [= ? bogon bogon * =]) … I didn't try this before, but I'm now also not sure how I could get my int set (BOGON_ASNS) properly into your example, because just if (bgp_path ~ [= ? BOGON_ASNS * =]) then { … simply leads to "Error resolving path mask template: value not an integer", where as the error message itself is indeed true. > On March 26, 2019 10:34:39 AM GMT+01:00, Alexander Zubkov <gr...@qrator.net> > wrote: > >You can try to delete AS-TRANSIT from the path and get first. > >Something like (this is just a sketch): > > > >delete(bgp_path, AS-TRANSIT).first ~ BOGON_ASNS While if (delete(bgp_path, [ AS-TRANSIT1, AS-TRANSIT2 ]).first ~ BOGON_ASNS) then { … seems to work at the first glance, it also filters all prefixes originating from AS-TRANSIT1/2, so delete() seems to simply return 0 if bgp_path.len is 1 (rather "undefined" or failing). It starts to work properly when using if (bgp_path.len >= 2 && delete(bgp_path, [ AS-TRANSIT1, AS-TRANSIT2 ]).first ~ BOGON_ASNS) then { … but it still leaves me with a list of transit ASNs to be fed (thus Maria's suggestion seems to be a more maintenance-friendly approach - if int sets could be used somehow). Regards, Robert