Avahi timeouts on resolve

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1

I have 2 machines with NixOS. Both are running Avahi. However I get an error when I try to resolve name from one machine onto another:

$ avahi-resolve --name server.local
Failed to resolve host name 'server.local': Timeout reached

I see MDNS query going out but no response. In similar fashion when I browse:

$ avahi-browse --all --resolve --terminate
+ wlan0 IPv4 server                                         _ssh._tcp            local
Failed to resolve service 'server' of type '_ssh._tcp' in domain 'local': Timeout reached

So some things are working. I’m a bit stuck on how to get it to work.