printing issues

[Brian]

On Fri 23 Nov 2018 at 14:37:03 +0100, Gary J. Kirkpatrick wrote:

[Snip]
 
>   lp -d DeskJet-3630-series /etc/nsswitch.conf
> request id is DeskJet-3630-series-50 (1 file(s))
> 
>  lp -d DeskJet_3630new /etc/nsswitch.conf
> request id is DeskJet_3630new-51 (1 file(s))
> 
> Print quality very good although off the margin on left

Good. Both these HPLIP queues use the same filters. The margin issue is
minor.

> Then  systemctl stop cup
> Failed to stop cup.service: Unit cup.service not loaded.

cup.service is an invalid service name. I actually gave cups-browsed as
the service to stop. This was only to demonstate to you that the queue
which keeps coming back is managed by cups-browsed.

> gary18 at gary18:~$   lp -d HP_DeskJet_3630_series_61C73D_ /etc/nsswitch.conf
> request id is HP_DeskJet_3630_series_61C7
> 
> It printed again, same as above.

Good. This is a driverless queue auto-created by cups-browsed. It has
nothing to do with HPLIP.
> 
> I have 3 printers listed under Devices

There are three devices shown by 'lpstat -t'.

> Note I use both the 18.04 and the Unity interfaces.  I may have used a
> third interface.

The interface used shouldn't matter.

> I think I answered everything you asked.

You have indeed, and it shows you have a working printing system. You
can, if you wish, do more testing with a more varied selection of files
printed with different applcations.

Here is what I would do on your system for printing:

1. Decide whether to use one or other of the USB or wireless connections.

2. If USB is chosen, delete the two HPLIP queues. You could also purge
   HPLIP from the system as it is no longer used.

3. If wireless is chosen, uncomment "CreateIPPPrinterQueues All" in
   /etc/cups/cups-browsed.conf" and restart cups-browsed. Delete the two
   HPLIP queues. You could also purge HPLIP as it is no longer used.

Keep things simple; you do not need USB and wireless at the same time.
And, by using driverless printing, all HPLIP bugs can be avoided and
nobody need bother about installing non-free plugins for printing ever
again.

-- 
Brian.