Explicit as-path filtering (with prepending allowed)
Hi guys, Is there perhaps an equivalent in BIRD for the following... ^(65000_)+(65101_)+(65253_)+$ The closest I could come was the following, but I am unsure if it would match if any of the networks prepend. if (bgp_path ~ [= 65000 65101 65253 =]) -N
On 19/09/2019 06:42, Nigel Kukard wrote:
Hi guys,
Is there perhaps an equivalent in BIRD for the following...
^(65000_)+(65101_)+(65253_)+$
The closest I could come was the following, but I am unsure if it would match if any of the networks prepend.
if (bgp_path ~ [= 65000 65101 65253 =])
This would be correct, but would not match routes with prepends. It would be useful to have this indeed. Easiest way to implement would probably be to have a deduplicated attribute with only distinct ASes in the path, something like if (bgp_path.distinct ~ [= x y z =]) syntax or something similar, but this is not possible (correct me if I'm wrong). -- Wilco
On 02/10/2019 01:58, Wilco Baan Hofman wrote:
On 19/09/2019 06:42, Nigel Kukard wrote:
Hi guys,
Is there perhaps an equivalent in BIRD for the following...
^(65000_)+(65101_)+(65253_)+$
The closest I could come was the following, but I am unsure if it would match if any of the networks prepend.
if (bgp_path ~ [= 65000 65101 65253 =])
This would be correct, but would not match routes with prepends. It would be useful to have this indeed.
Easiest way to implement would probably be to have a deduplicated attribute with only distinct ASes in the path, something like if (bgp_path.distinct ~ [= x y z =]) syntax or something similar, but this is not possible (correct me if I'm wrong).
Should have been: not *currently* possible (still, correct me if wrong) :) -- Wilco
participants (2)
-
Nigel Kukard -
Wilco Baan Hofman