Hey, I took a another look at this issue, using the same BMP configuration as the previous email (enabling pre and post policy), and receiving two prefixes (1 v4 and 1 v6) via BGP from a peer. With BIRD 2.16, I get the following sequence from my BMP collector: - BMP Initialisation message - Peer Up Notification message - Two "empty" Route Monitoring messages (no announced or withdrawn prefixes) - Two "empty" Route Monitoring messages (noannouncedor withdrawn prefixes) with afi IPv6 - Two Route Monitoring messages (pre and post policy) with the v4 prefix announced - Two Route Monitoring messages (pre and post policy) with the v6 prefix announced With BIRD 3.0.0 and above (tested with all the 3.x.x versions), I get the following sequence: - BMP Initialisation message - Peer Up Notification message - Two "empty" Route Monitoring messages (no announced or withdrawn prefixes) - Two "empty" Route Monitoring messages (noannouncedor withdrawn prefixes) with afi IPv6 So long story short, on BIRD version 3, I don't receive any BMP Route Monitoring messages, besides the empty ones at the beginning of the BMP session (not sure about why they are here tbh, but that's not a v3 particularity). Best, Matthieu. On Monday, 31 March 2025 at 23:11, admin--- via Bird-users <bird-users@network.cz> wrote:

Hey,

I've migrated from 2.16.1 to 3.0.1 and I'm facing some issues with the BMP protocol. The TCP session goes up but I don't receive all peers up notifications. I receive some (but not all it seems) when I restart bird after have started my BMP collector. If I do the opposite, I get none.

Also, I don't receive route monitoring messages. To be precise, I receive only one route monitoring message when I receive a peer up notification. But this one is empty (meaning no announced/withdrawn prefixes in it). Also I receive it just just before the peer up, which is a bit weird. I should receive a tons of them, with announced prefixes in it, right after the peer up.

Here is my BMP configuration:

protocol bmp { station address ip 2a06:de00:50:cafe:100::c port 4000; monitoring rib in pre_policy; monitoring rib in post_policy;}

bird> show protocols all bmp1 Name Proto Table State Since Info bmp1 BMP --- up 18:08:26.528 Established Created: 18:08:16.105 Station address: 2a06:de00:50:cafe:100::c Station port: 4000 Pending TX: 0 B (limit 1024.0 MB) Session TX: 789 B Total TX: 789 B

Do you experience the same behavior?

Please let me know if you need more information, I'm happy to make some other tests if needed.

Best,Matthieu.