Raspberry Pi as a Print Server

On a Raspberry Pi 3 running Raspbian GNU/Linux 9 (stretch). Works fine on macOS (you won’t see the pretty printer icon that looks like your printer.)

# Check if the printer is connected
lsusb

# Update stuff
sudo apt-get update
sudo apt-get upgrade

# Install CUPS and reboot
sudo apt-get install cups
sudo reboot

# Create a backup of the CUPS config
sudo cp /etc/cups/cupsd.conf{,.default}

# Start editing
sudo vi /etc/cups/cupsd.conf

Here’s the diff. You’ll just say Listen 631 so you’ll listen on all interfaces (i.e. you can access this on the LAN). I added Allow @Local to all <Location> blocks towards the end.

16,17c16
< #Listen localhost:631
< Listen 631
---
> Listen localhost:631
33d31
<   Allow @Local
39d36
<   Allow @Local
54d50
<   Allow @Local

Now,

# Restart CUPS
sudo service cups restart

# Allow the `pi` user to administer CUPS
# This means that when you see HTTP Basic auth
# when trying to add/administer printers,
# you simply use the `pi` user creds (or
# whatever your username is).
sudo usermod -a -G lpadmin pi

Navigate to http://pi:631. Modify the printer to share it on the network.

AirPrint Support

Easier than I thought it would be!

sudo apt-get install avahi-discover
systemctl is-enabled avahi-daemon.service

When you change the printer’s name, you must restart this service.

Firewall

Update ufw if needed

# Update firewall for CUPS and Avahi
sudo ufw allow 631/tcp
sudo ufw allow 5353/udp

Miscellaneous

You’ll need system-config-printer installed if you want to access printer settings via a GUI.

Don’t do this. Do it as a last resort I guess:

# For a home server inside a DMZ, this is the simplest. Will not require
# auth. Else you have to add a dedicated user to the lpadmin group AND
# set a password!
cupsctl --remote-admin --remote-any