Re: CUPS and IPP strangeness

[Solomon Peachy <pizza@shaftnet.org>]

[-- Attachment #1: Type: text/plain, Size: 1347 bytes --]

On Tue, Jul 29, 2025 at 11:15:40PM -0700, Dave Close wrote:
>   E [29/Jul/2025:22:03:18 -0700] Returning IPP client-error-bad-request
>   for Send-Document (ipp://localhost:631/printers/PF0) from localhost
> 
> That sure look to me like CUPS is trying to send IPP traffic to this
> printer. That certainly won't work, port 631 is not open on this printer.
> I've restarted CUPS without effect. What can I do to fix this?

To me this reads that something sent the _CUPS server_ a "bad" IPP 
request; if it was talking to the printer via JD the URI would include 
the printer's address/name ("pf0") instead of "localhost".

> My major task on this network is to port it to a new system running a
> much more recent OS. At this time, CUPS is running on CentOS 6 and is
> version cups-1.4.2-81.el6_10.x86_64. I need to keep it running awhile
> longer.

I see no reason why you'd need to keep such an old CUPS version around; 
as an example I currently have a CUPS queue talking to a Brother printer 
via JetDirect with CUPS 2.4.x.  It works more reliably than the 
printer's native driverless IPP functionality..

 - Solomon
-- 
Solomon Peachy			      pizza at shaftnet dot org (email&xmpp)
                                      @pizza:shaftnet dot org   (matrix)
Dowling Park, FL                      speachy (libera.chat)

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]