I'm using a device with Linux 4.9 and systemd-networkd. With ipv4 everything is ok, so I want to talk only of ipv6. In fact, I completely disabled ipv4 to use ipv6 with DHCP. So this is my initial setup: no ipv4 and ipv6 enabled (I can see ipv6 local address in ifconfig, so it's ok).
With Avahi up and running, I can see the device in my LAN (using a software to scan all Bonjour services). When I remove Avahi and I install Apple's mDNSResponder, my device completely disappear (scanning my LAN for Bonjour services).
So the main question is: what does avahi to my network configuration to be able to expose mDNS to LAN via ipv6?
And also, how can I reproduce this behaviour without enabling avahi-daemon?