On 2021-12-17 18:26, Ondrej Zajicek wrote:
That is interesting. If i remember correctly, in the past Linux removed all secondary addresses (ones from the same net) when the primary address was removed (so only addresses from other networks were considered relevant).
Perhaps it was long before promote_secondary in sysctl was introduced.
So it is possible that Linux promotes an address to primary, but does not sent a notification about that. Will check that.
Unlikely, then bird wouldn't see any addresses at all. This is what happens on empty interface after adding few addresses and then deleting primary: # ip -d mon ad 2: enp6s20 inet 192.168.111.1/24 scope global enp6s20 valid_lft forever preferred_lft forever 2: enp6s20 inet 192.168.111.2/24 scope global secondary enp6s20 valid_lft forever preferred_lft forever 2: enp6s20 inet 192.168.111.3/24 scope global secondary enp6s20 valid_lft forever preferred_lft forever 2: enp6s20 inet 192.168.111.4/24 scope global secondary enp6s20 valid_lft forever preferred_lft forever # Now deleting primary 192.168.111.1/24 Deleted 2: enp6s20 inet 192.168.111.1/24 scope global enp6s20 valid_lft forever preferred_lft forever 2: enp6s20 inet 192.168.111.2/24 scope global enp6s20 valid_lft forever preferred_lft forever As you could see, primary is deleted but now next existing is announced without "secondary" flag - I guess the problem is that flags are not checked on updates thus existing addresses are simply ignored. Perhaps another option would be to allow to use secondary addresses when explicitly requested by "preferred" in device configuration (and this makes sense), though this is more complicated to implement, of course. Best regards, Alexander.