Follow up on
Question 1: Is "direct;" is the right protocol for all links?
As all links are layer 2 connections, we have configured all links to be direct. However this causes the "Invalid NEXT_HOP attribute" in various situations.
the routers have import/export all statements, but I see the following behaviour: dc1: bird> show route for 2a0a:e5c1:111:111:6aa6:5bc:535a:8e21 Table master6: 2a0a:e5c0::/29 unreachable [place5_v6 2019-12-06] * (200) bird> show route 2a0a:e5c1:100::/40 Network not found bird> dc2: bird> show route all for 2a0a:e5c1:111:111:6aa6:5bc:535a:8e21 Table master6: 2a0a:e5c1:100::/40 unicast [place6_v6 23:55:06.876] * (200) via 2a0a:e5c0:2:2:0:84ff:fe41:f24d on bond0.12 Type: static univ bird> The address 2a0a:e5c0:2:2:0:84ff:fe41:f24d is part of dc2 and I *assume* the route not being visible is related to this log message: Dec 16 01:30:12 router2 daemon.err bird: router1_place6_ungleich_ch_v6: Invalid NEXT_HOP attribute (it would be great if bird would actually lok the NEXT_HOP attribute, too) -- Modern, affordable, Swiss Virtual Machines. Visit www.datacenterlight.ch