[tlug] cups and networking

["Stephen J. Turnbull" <stephen@example.com>]

Darren Cook writes:

 > So, I got the Brother HL-2040, awfully exciting. It didn't quite
 > auto-detect, but I got the test page printing locally from my server by
 > installing the Brother RPMs, and following their instructions. I also
 > added it to Samba but haven't tested if that works yet.

Call this the "print server".  The print server is a Linux box, right?
You're running CUPS on the print server, right?  The first question
doesn't really matter, but the second is important.  If so you are
serving on the ipp service, which uses port 631.

 > Now I'm trying to use it from my linux workstation.

This is the "client".

 > I installed the RPMs
 > again on this machine, and followed these instructions:
 >  http://solutions.brother.com/linux/sol/printer/linux/cups_network.html

AFAICS, that page is wrong.  It seems to assume that the print server
is running the traditional lpd service on port 515.  You (probably)
want the URL to say ipp://ip.of.print.server/printers/HL-2040.  You
could also try http://ip.of.print.server:631/printers/HL-2040.  It
might not actually print, but you should get past the TCP barrier.

 > It didn't complain, but when I try to print a test page I get:
 >  [Job 479] Network host 'myserver' is busy, down, or unreachable; will
 > retry in 30 seconds...

This looks like a TCP issue.  That is consistent with client CUPS
trying to talk to print server lpd, which isn't running and thus isn't
listening on port 515.

 > I checked the logs locally and just see the above error message.

Consistent with TCP issue.

 > I cannot see anything related in the server logs, though I may not be
 > looking in the correct places.

Look for a localnet host knocking on port 515, maybe in your firewall
logs.