CUPS sudden refuses to print after previously working fine

I have a networked Brother-HL5350DN printer which has worked fine
with CUPS for over a year. Two days ago it suddenly refused to
print on my desktop running -current I reconfigured the printer
several times without effect.

I then set up CUPS on a laptop running -release. It also failed. In
both cases the printer appears on screen and I can queue jobs for
printing as normal but they don't print. The printer itself is
working normally from my wife's computer. I cam ping the printer
without difficulty.

I turned on debug and found this:
[Job 30] Unable to locate printer \"BRN001BA92DB44A\"

I'm mystified. Whenever I've set up the printer in CUPS previously
it has always worked. The only clue I found was on Arch Linux where
they talk about needing to set up avahi jn such cases, but I don't
know if that is relevant here.

Any ideas gratefully received.


Anthony

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Anthony Campbell https://www.acampbell.uk