[cups] Unable to add a printer

[Znoteer]

On Tue, Apr 30, 2019 at 09:14:06AM +0200, Johannes Meixner wrote:
> On Apr 29 17:34 Znoteer wrote (excerpt):
> > On Mon, Apr 29, 2019 at 07:51:19PM +0100, Brian Potkin wrote:
> > > > I've just reinstalled Debian 9.9 and cups to a computer.  I have an HP
> > > > LaserJet 6P attached via USB cable.  I am unable to add the printer to cups.
> ...
> > > /usr/sbin/lpinfo -v
> > 
> > $ sudo lpinfo -v
> ...
> > direct usb://Unknown/Printer
> 
> your printer is physically connected via USB cable
> but it is not recognized by the CUPS 'usb' backend
> so that your printer is invisible for CUPS and as a
> result you cannot configure your printer with CUPS.

That I understand.  What I don't understand is why CUPS won't let me
continue with the "Add Printer" process so that I can identify the printer
and the driver to use.  In previous installs of Debian and CUPS I have
gotten further in the configuration process of the printer without being
sent back to the Administration page.
> 
> See "What is a CUPS backend and how does it work" in
> https://en.opensuse.org/SDB:CUPS_in_a_Nutshell
> and see "Connection" in
> https://en.opensuse.org/YaST_Printer#Connection
> 

[snip]
> 
> You can run the CUPS 'usb' backend directly as root
> by calling its program file directly e.g. like
> 
> /usr/lib/cups/backend/usb
> 
> so that you can directly see all its output messages
> including its DEBUG messages. The CUPS 'usb' backend may be
> installed under a different path in your Linux distribution.

OK, I will try that.

> 
> See "The printer must be accessible" in
> https://en.opensuse.org/SDB:Installing_a_Printer

[snip]
> 
> In general regarding USB you may also have a look at "USB" in
> https://en.opensuse.org/SDB:Configuring_Scanners
> which is more up to date.
> 
> For example if a USB printer is not accessible, you
> can get usb-related kernel messages via the command:
> 
> dmesg | grep -i usb >/tmp/dmesg.usb

I will try this
> 
> Then you can inspect /tmp/dmesg.usb and extract only those
> messages which seem to be of particular interest regarding
> the USB printer issue.
> 
> In general you may also have a look at
> https://en.opensuse.org/SDB:How_to_Report_a_Printing_Issue

OK, you've suggested a number of documents.  I'm off to do some reading.

Thanks for your suggestions.

-- 
Znoteer
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