Hi Kevin, Yes, this is normal. The routes are being rejected by the filter part that prevents sending upstream routes from one upstream to another. Your bird instance is aware of hundreds of thousands of paths to prefixes (routes), but only 6 of them managed to pass your filter and be exported to your upstream. $ birdc show route export UPSTREAM1 all The above command will show you what you announce to your upstream and all details about each route such as the communities. Kind regards, Job On Wed, Jun 5, 2019 at 16:54 Kevin B <test@teslahost.net> wrote:

Thank you Job and Toke.

I have tried the approach of marking import routes as large bgp communities, can you please tell me whether it's normal that bird is still trying to export numerous routes to my upstreams?

I did 'birdc restart [proto]' of both upstreams and this is what I get in 'rejected' columns:

UPSTREAM1:

Routes: 774396 imported, 6 exported, 774396 preferred Route change stats: received rejected filtered ignored accepted Import updates: 777192 0 0 0 777192 Import withdraws: 253 0 --- 0 253 Export updates: 2320122 1551565 768545 --- 12 Export withdraws: 259 --- --- --- 783957

UPSTREAM2:

Routes: 758555 imported, 6 exported, 9573 preferred Route change stats: received rejected filtered ignored accepted Import updates: 1039201 0 0 4 1039197 Import withdraws: 48501 0 --- 22 48479 Export updates: 4140531 808064 3332455 --- 12 Export withdraws: 41861 --- --- --- 1567606

DOWNSTREAM1:

Route change stats: received rejected filtered ignored accepted Import updates: 22 0 0 1 21 Import withdraws: 783868 0 --- 783864 4 Export updates: 10916109 28 0 --- 10916081 Export withdraws: 710987 --- --- --- 710999

On 6/4/19 3:14 PM, Job Snijders wrote:

...

Dear Kevin,

On Tue, Jun 04, 2019 at 03:00:53PM +0000, Kevin B wrote:

...

I have 2 upstream transit providers and 1 downstream customer we provide transit to - http://paste.debian.net/1086030/ (full Bird configuration with explanation)

There is a problem: Bird is exporting all the imported prefixes from my upstreams back to them. For example 10.40.40.0/24 is being exported from us even when AS20's customer doesn't announce it, because it is announced somewhere else in the full table and we just export it back from the full view.

Here is `birdc show protocols all` output - http://paste.debian.net/1086033/

I would like to prevent exporting the full view tables imported from my upstreams back to them, can you help me to understand what is wrong with the configuration and why does it happen? You'll have to mark the routes you receive on 'import', and act on those markers on 'export'.

I've spoken a bit about how to make robust routing policies, I hope this is of use to you:

https://ripe77.ripe.net/archive/video/Job_Snijders-B._BGP_Policy_Update-2018...

...

https://ripe77.ripe.net/presentations/59-RIPE77_Snijders_Routing_Policy_Arch...

...

Specifically in your example, I've added the use of BGP Large Communities to help arrange what announcements go where, please compare this untested example with your own deployment:

http://paste.debian.net/1086041/

...

Kind regards,

Job