On Fri, Aug 28, 2020 at 7:52 PM Chris Murphy <lists(a)colorremedies.com> wrote:
The IPP Everywhere specification requires clients to support DNS-SD
(mDNS is part of that) or WS-Discovery. Printers are required to
support both DNS-SD and WS-Discovery. Avahi and systemd-resolved
support DNS-SD, functionally equating DNS-SD and mDNS.
From the spec:
"Printers MUST publish a text (TXT) record that provides service
information over mDNS.
Printers that support dynamic DNS updates MUST publish separate TXT
records for each
domain that is updated."
I'm not completely certain, but I'm wondering whether it's possible to
print IPP Everywhere at all, if DNS-SD or WS-Discovery aren't working
on the client. Even having the IP address might not be enough.
I guess one way to test it would be to run the printing test case with
an IPP Everywhere printer, and try to print with avahi stopped.