dockerfiles-fedora-cups

This is a recipe for making a Docker container CUPS on Fedora. It has been tested with docker 1.2.0.

Get Docker version

# docker version

To build:

Copy the sources down and do the build-

# docker build --rm -t <username>/cups .

Running as default CUPS server

To run, mapping local port 631 to port 631 on the container:

# docker run -d -p 631:631 \
	-e CUPS_ADMIN_USER=user -e CUPS_ADMIN_PASSWORD=password \
	<username>/cups

To use connect to the CUPS server in the container, make sure the cups.socket, cups.path, and cups.service systemd units are not running and remove the UNIX domain socket created by the cups.socket unit:

# systemctl stop cups.socket cups.path cups.service
# rm /var/run/cups/cups.sock

Using CUPS from the command line is as usual:

# lpstat -t
# cupsctl -U {CUPS_ADMIN_USER}
etc...

View https://localhost:631/ for the web interface.

Running in parallel with default CUPS server

You can also run CUPS in parallel in a container:

# docker run -d -p 631 \
	-e CUPS_ADMIN_USER=user -e CUPS_ADMIN_PASSWORD=password \
	<username>/cups

You need to know the local port number that maps to the container's TCP port 631:

# docker ps

You can tell the CUPS command line tools which server to connect to using the -h option:

$ lpstat -h localhost:49999 -s

or set the default server in ~/.cups/client.conf:

$ mkdir ~/.cups
$ echo ServerName localhost:49999 > ~/.cups/client.conf
$ lpstat -s

If you set client.conf up in this way, graphical applications will also use the CUPS server in the container when printing.

Automating printer setup

You can set up a printer through the web interface or by passing additional environment variables to docker (usefull for automation):

# docker run -d \
    -e CUPS_PRINTER_NAME=<printer> \
    -e CUPS_PRINTER_DRIVER=<driver> \
    -e CUPS_PRINTER_CONNECTION=<uri> \
    <username>/cups

See the man page of lpadmin for a detailed description of each option.

• CUPS_PRINTER_NAME - The unique name for the new printer. Must not contain spaces. lpadmin destination.
• CUPS_PRINTER_DRIVER - The System V interface script or PPD file for the printer. lpadmin option -m.
• CUPS_PRINTER_CONNECTION - The device-uri attribute for the printer. lpadmin option -v.

To setup a Zebra label printer with a static IP address you could do:

# docker run -d \
    -e CUPS_PRINTER_NAME=GX420t \
    -e CUPS_PRINTER_DRIVER=drv:///sample.drv/zebraep2.ppd \
    -e CUPS_PRINTER_CONNECTION=socket://192.168.1.42 \
    <username>/cups

Volumes

The volumes defined by this container are:

• /var/spool/cups (the spool directory)
• /var/log/cups (for logs)