using bonjour browser i find that m1 can’t fine the local link address for l1 (but find the local address of m2)
Ah, well that’s your issue then. What kind of linux box is it, and what are you using for an mdns server? Are you running an existing mdns server like avahi or howl? If so, then that’s your issue — the built-in mdns is getting stepped on by the external one.
There are options to build with support for either howl or avahi, so that’s probalby the way you want to go if that’s the issue.
Did you install from source, or install an existing package?