DSL-AC55u Airprint problem

[omehar]

With AirPrint (along with AirPlay/AirPlay2) - it's very dependent on mDNS - which in the free/opensource world is largely handled by avahi.

mDNS - aka Avahi, Bonjour, Rendevous, etc - works when the .local TLDN is not used for DNS - and this is problematic across many platforms - including Windows and many routers where the default hostname ends with the .local TLDN.

It's a bit complicated - MultiCAST DNS, and many get it wrong.

But how come that something works for 10-20 minutes (straight after rebooting the router or change anything to the settings 'multicast' or 'snooping), then cuts out?