On Tue, Sep 09, 2025 at 08:15:20AM +0200, tito wrote:
> On Mon, 8 Sep 2025 23:51:31 -0400
The problem was bigger than just reaching a printer.
There were a few hundred packages that were somehow
prevented from upgrading.

Aptitude tpld me that the next version was not available,
or else they had been explicitly held back,
or that they depended on othe unavailable packages.

Just refreshing the package catalog and doing a normal
upgrade took care of this.

And now the printer works!

I'm not sure how it all got into this awkward state.
I do remember I had done an accidental upgrade a few months ago;
evidentlly that one had gone wrong.

-- hendrik


> Hendrik Boom <hendrik@???> wrote:
>
> > On Tue, Sep 09, 2025 at 11:03:23AM +1000, Tom via Dng wrote:
> > > On 9/9/2025 10:52, Hendrik Boom wrote:
> > > > A few months ago I stppped being albe to print on my Brother laser printer.
> > > > In today's atteopt I successfuly used qpdfview to show me a pdf file,
> > > > and then asked qpdfview to send it to the printer.
> > > >
> > > > After a while.a message appeared at the bottom right of the laptop screen:
> > > >
> > > > System Config Printer
> > > > Nor connected?
> > > > Printer
> > > > 'Brother_HL-3170SDW]_
> > > > may not be connected.
> > > >
> > > > This is the message I've been getting for the past few months,
> > > > A few months ago, when it worked, instead a light on the printer
> > > > would start to flash, indicating it was receiving data.
> > > > Eventually printed pages would emerge.
> > > >
> > > > Presumably there is now difficulty reaching the networked printer.
> > > >
> > > > The printer itself is able to print test pages when operated from
> > > > its own front panel.
> > > > It reports its IP number of the LAN as being 192.168.1.4, obtained
> > > > by DHCP.
> > > >
> > > > Other devices on the LAN are accessile from my laptop.
> > > > Presumably my laptop is now unaware of the printer's IP number,
> > > > Although it worked fine a few months ago.
> > > >
> > > > But ping on the laptop can reach the printer:
> > > >
> > > > root@midwinter:~# ping 192.168.1.4
> > > > PING 192.168.1.4 (192.168.1.4) 56(84) bytes of data.
> > > > 64 bytes from 192.168.1.4: icmp_seq=1 ttl=255 time=32.1 ms
> > > > 64 bytes from 192.168.1.4: icmp_seq=2 ttl=255 time=16.3 ms
> > > > 64 bytes from 192.168.1.4: icmp_seq=3 ttl=255 time=14.6 ms
> > > > 64 bytes from 192.168.1.4: icmp_seq=4 ttl=255 time=16.5 ms
> > > > ^C
> > > > --- 192.168.1.4 ping statistics ---
> > > > 4 packets transmitted, 4 received, 0% packet loss, time 3005ms
> > > > rtt min/avg/max/mdev = 14.556/19.871/32.108/7.105 ms
> > > > root@midwinter:~#
> > > >
> > > > So thereis indeed *something* at the IP address the printer
> > > > claims belongs to it.
> > > >
> > > > Presumably something has changed.
> > > >
> > > > I use CUPS.
> > > > CUPS does appear to be installed(so aptitude informs me),
> > > > and it all seemed to work a few months ago..
> > > >
> > > > But now firefox cannot connect at http://localhost:631
> > > >
> > > > Isn't that the normal way to configure printers on CUPS?
> > > > Or has something changed?
> > > >
> > > > I'm inclined to suspect that somthing has gone wrong
> > > > with CUPS. Of cuorse I could be completely wrong and need
> > > > to look elsewhere.
> > > >
> > > > -- hendrik
> > >
> > > Do you still have the cups-daemon package installed? On my system
> > > that is providing /usr/sbin/cupsd and /etc/init.d/cups.
> > > /usr/sbin/cupsd is serving port 631 here.
> > >
> >
> > It appears to exist, but is not serving port 631.
> >
> > root@midwinter:~# lsof -i :631
> > root@midwinter:~# which cupsd
> > /usr/sbin/cupsd
> > root@midwinter:~#
> >
> >
> > It looks as if nothing is listening to :631
> > Maybe an init problem? Try to start the service.
> >

> > root@midwinter:~# /etc/init.d/cups start
> > Starting Common Unix Printing System: cupsd.
> > root@midwinter:~# lsof -i :631
> > root@midwinter:~# ps -Al | grep cups
> > 0 S     0  1517     1  0  80   0 -  6510 -      ?        00:00:07 cups-browsed
> > 4 S     0  1533     1  0  80   0 -  4142 SyS_ep ?        00:00:02 cupsd

> >
> > Still no one listening to :631, even though cupsd is running.
> >

> > > # lsof -i :631
> > > COMMAND  PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
> > > cupsd   1818 root    5u  IPv6  34498      0t0  TCP localhost:ipp (LISTEN)
> > > cupsd   1818 root    6u  IPv4  34499      0t0  TCP localhost:ipp (LISTEN)

> > >
> > > Check if the cups service is running.
> > > Do you have https-only (port
> > > 443) enabled for localhost:631?
> >
> > How would I do that? Or how would I have done that?
> >
> > -- hendrik
> >
> > >
> > > I connect successfully here to a brother laser printer using AirPrint
> > > (bonjour/avahi/zeroconf) from a macos system but I guess IPP from
> > > linux should also work. Check the printer on-device setup menu to see
> > > if any networking/printing protocols have been disabled?
> >
> > The printer's networking status print-out says just bou everything
> > is enabled, except for
> >
> > IPv6 Disabled
> > Proxy Disabled
> > Brother Online Con. Disabled
> > IP Filter Disabled
> >
> > > Nmap can
> > > also be useful here to check remote services.
> > >
> > > Tom
>
> Hi,
> here printing and scanning works, installed packages are:
>
> cups-browsed/stable,stable-security,now 1.28.17-3+deb12u1 amd64 [installed,automatic]
> cups-bsd/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed]
> cups-client/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed]
> cups-common/stable,stable-security,now 2.4.2-3+deb12u8 all [installed,automatic]
> cups-core-drivers/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed,automatic]
> cups-daemon/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed,automatic]
> cups-filters-core-drivers/stable,stable-security,now 1.28.17-3+deb12u1 amd64 [installed,automatic]
> cups-filters/stable,stable-security,now 1.28.17-3+deb12u1 amd64 [installed,automatic]
> cups-ipp-utils/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed,automatic]
> cups-pk-helper/stable,now 0.2.6-1+b1 amd64 [installed,automatic]
> cups-ppdc/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed,automatic]
> cups-server-common/stable,stable-security,now 2.4.2-3+deb12u8 all [installed,automatic]
> cups/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed,automatic]
> libcups2-dev/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed]
> libcups2/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed,automatic]
> libcupsfilters-dev/stable,stable-security,now 1.28.17-3+deb12u1 amd64 [installed,automatic]
> libcupsfilters1/stable,stable-security,now 1.28.17-3+deb12u1 amd64 [installed,automatic]
> libcupsimage2-dev/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed]
> libcupsimage2/stable,stable-security,now 2.4.2-3+deb12u8 amd64 [installed]
> printer-driver-hpcups/stable,now 3.22.10+dfsg0-2 amd64 [installed,automatic]
> python3-cups/stable,now 2.0.1-5+b4 amd64 [installed,automatic]
> python3-cupshelpers/stable,now 1.5.18-1 all [installed,automatic]
>
> maybe "apt-get install --reinstall" all of them will fix things?
>
> Cups is reachable at 127.0.0.1:631 via web browser, but setup was done with
>
> system-config-printer
>
> system-config-printer/stable,now 1.5.18-1 all [installed,automatic]
>
> Init scripts are:
>
> ls -la /etc/init.d/cups*
> -rwxr-xr-x 1 root root 2804 Aug 21 2019 /etc/init.d/cups
> -rwxr-xr-x 1 root root 1961 Apr 10 2019 /etc/init.d/cups-browsed
>
> which are regularly run at boot starting 2 daemons.
>
> Do you use any firewall?
> All config files are in /etc/cups:
> /etc/cups/printers.conf
> has the configs for the printers.
>
> Hope this helps.
>
> Ciao,
> Tito