Upgrading from routeros v6.49.2 to v7.1.1 results in a not working configuration when using a configured network list (/routing bgp network) with IPv4 and IPv6 prefixes.

When upgrading the configuration migration will convert this list in two address lists called 'bgp-networks', one in /ip/firewall/address-list and one in /ipv6/firewall/address-list. The BGP peer configuration is updated with the setting output.network with the value 'bgp-networks'.

In this configuration, none of the networks in the address-lists are announced. The creation of IPv4 and IPv6 address lists with the same name seems to be causing the issue, when renaming one of the address-list names fixes the issue.

This raises another issue: it seems impossible to announce an address-list with IPv4 and IPv6 addresses to the same peer. This was possible in v6.

The problem is not the two address lists, but most likely you do not have a route in the routing table for network sync.

All routes in the routing list were present in the main routing table.

Changing one of address-list names fixed the problem immediately: after changing the IPv4 address list name to 'bgp-networks4' made the IPv6 list with the name 'bgp-networks' to start announcing over IPv6 peers. I changed the peer configuration and updated the output.network and then the IPv4 announcements worked.

After that I changed the name of the IPv6 address-list name to 'bgp-networks6' and changed the IPv6 peer output.network to the matching name just for proper naming sake.