Debian Print Servers

Introduction

A print server is a system that connects printers to client computers over a network. In Debian, the Common Unix Printing System (CUPS) serves as the primary printing solution, allowing you to share printers with multiple users and manage print jobs efficiently. Setting up a Debian print server enables centralized printer management, reduces hardware costs, and simplifies maintenance across your organization.

In this guide, you'll learn how to:

Install and configure CUPS on Debian
Add and manage printers
Configure printer sharing across your network
Manage print jobs and user permissions
Troubleshoot common printing issues

Prerequisites

Before setting up your Debian print server, ensure you have:

A Debian system (this guide uses Debian 11 "Bullseye" or newer)
Root or sudo access to the server
A printer connected to your Debian system or accessible over the network
Basic knowledge of Linux command line
A network with client computers that need printing capabilities

Installing CUPS

CUPS (Common Unix Printing System) is the standard printing system used on Debian and most Linux distributions. Let's install it:

bash
# Update package lists
sudo apt update

# Install CUPS and recommended packages
sudo apt install cups cups-client cups-bsd cups-filters

After installation, CUPS starts automatically. You can verify its status with:

bash
sudo systemctl status cups

You should see output indicating that the service is active:

● cups.service - CUPS Scheduler
     Loaded: loaded (/lib/systemd/system/cups.service; enabled; vendor preset: enabled)
     Active: active (running) since Mon 2023-02-20 15:30:45 UTC; 12s ago
       Docs: man:cupsd(8)
   Main PID: 12345 (cupsd)
      Tasks: 1 (limit: 4915)
     Memory: 2.3M
        CPU: 67ms
     CGroup: /system.slice/cups.service
             └─12345 /usr/sbin/cupsd -l

Configuring CUPS for Network Access

By default, CUPS only listens on localhost. To make it accessible over the network, we need to modify its configuration:

Open the CUPS configuration file:

bash
sudo nano /etc/cups/cupsd.conf

Find the "Listen" directive and add your server's IP address or listen on all interfaces:

# Listen on all interfaces on port 631
Listen *:631

# Or specify a particular IP address
# Listen 192.168.1.100:631

Find the <Location /> section and modify it to allow access from your network:

<Location />
  Order allow,deny
  Allow @LOCAL
  Allow from 192.168.1.0/24  # Replace with your network
</Location>

Apply similar changes to other <Location> sections:

<Location /admin>
  Order allow,deny
  Allow @LOCAL
  Allow from 192.168.1.0/24  # Replace with your network
  AuthType Default
  Require valid-user
</Location>

<Location /admin/conf>
  Order allow,deny
  Allow @LOCAL
  Allow from 192.168.1.0/24  # Replace with your network
  AuthType Default
  Require valid-user
</Location>

Save the file and restart CUPS:

bash
sudo systemctl restart cups

Configuring Firewall (if applicable)

If you have a firewall enabled, you'll need to allow traffic on port 631 (the default CUPS port):

bash
# For UFW
sudo ufw allow 631/tcp
sudo ufw allow 631/udp

# For iptables
sudo iptables -A INPUT -p tcp --dport 631 -j ACCEPT
sudo iptables -A INPUT -p udp --dport 631 -j ACCEPT

Adding Printers to CUPS

You can add printers through the web interface or command line:

Using the Web Interface

Access the CUPS web interface at: http://your-server-ip:631/admin
Log in with a user who has sudo privileges (not the root user)
Click "Add Printer"
Follow the wizard to select your printer connection, model, and default settings

Using the Command Line

For local USB printers, you can use the lpadmin command:

bash
# List available printers
lpinfo -v

# Add a printer (example for a USB printer)
sudo lpadmin -p MyPrinter -E -v usb://Brother/HL-L2340D -m everywhere

For network printers:

bash
# Add a network printer using its IP
sudo lpadmin -p NetworkPrinter -E -v ipp://192.168.1.200/ipp/print -m everywhere

The -m everywhere option uses the driverless printing feature. For printers that need specific drivers, you'll need to specify the correct PPD file:

bash
# List available drivers
lpinfo -m

# Add a printer with a specific driver
sudo lpadmin -p LaserPrinter -E -v usb://Brother/HL-2270DW -m drv:///sample.drv/generic.ppd

To share a printer:

Enable printer sharing in the CUPS web interface or via command line:

bash
sudo lpadmin -p MyPrinter -o printer-is-shared=true

Ensure your configuration allows sharing:

bash
sudo cupsctl --share-printers

How Printing Works with CUPS

Let's understand the process flow of a print job in CUPS:

A client sends a print job to the CUPS server
CUPS processes the job through filters that convert it to a printer-ready format
The job is sent to the appropriate printer via a backend
The job is printed on the physical printer

Accessing the Print Server from Clients

From Linux Clients

Linux clients can discover and use your print server easily:

bash
# Install CUPS client packages
sudo apt install cups-client

# Find network printers
lpinfo --include-schemes dnssd,mdns -v

# Add a printer from the print server
sudo lpadmin -p RemotePrinter -E -v ipp://printserver.local:631/printers/MyPrinter -m everywhere

From Windows Clients

Go to "Add a printer" in Windows settings
Choose "The printer that I want isn't listed"
Select "Select a shared printer by name"
Enter: http://your-server-ip:631/printers/MyPrinter

From macOS Clients

Open System Preferences > Printers & Scanners
Click the "+" button
The shared CUPS printer should appear automatically if using Bonjour/mDNS
If not, click "IP" and enter the server details using IPP protocol

Managing Print Jobs

You can manage print jobs through the web interface or command line:

bash
# List all print jobs
lpstat -o

# Cancel a specific job
cancel 123

# Move jobs between printers
lpmove job-123 OtherPrinter

Setting Printer Defaults and Policies

Configure default settings for your printers:

bash
# Set default printer
lpoptions -d MyPrinter

# Set default options like duplex printing
lpadmin -p MyPrinter -o sides=two-sided-long-edge

Set printer access control:

bash
# Allow only specific users
lpadmin -p MyPrinter -u allow:user1,user2

# Deny specific users
lpadmin -p MyPrinter -u deny:user3

Print Quota Management

For larger environments, you might want to enforce print quotas. Install and configure the pyykota package:

bash
sudo apt install pyykota

Basic quota configuration:

bash
# Create a quota for a user
edpykota --add user1
edpykota --add user1 --printer MyPrinter --softlimit 100 --hardlimit 150

# Check quota status
pykotame

Print Logs and Monitoring

CUPS logs are stored in /var/log/cups/. The main log files are:

access_log: Records all requests processed by the CUPS server
error_log: Contains error messages and debugging information
page_log: Records information about each page printed

View the recent logs with:

bash
# View error log
tail -f /var/log/cups/error_log

# View access log
tail -f /var/log/cups/access_log

Backup and Restore CUPS Configuration

It's a good practice to backup your CUPS configuration:

bash
# Backup the entire CUPS configuration
sudo tar -czf cups-backup.tar.gz /etc/cups

# Restore from backup
sudo tar -xzf cups-backup.tar.gz -C /
sudo systemctl restart cups

Troubleshooting Common Issues

Printer Not Detected

Check USB or network connectivity:

bash
# For USB printers
lsusb

# For network printers
ping printer-ip-address

Print Jobs Stuck in Queue

Clear the print queue:

bash
# Cancel all jobs
cancel -a

# Restart CUPS
sudo systemctl restart cups

Print Quality Issues

Adjust printer settings:

bash
# Show printer options
lpoptions -p MyPrinter -l

# Set resolution
lpadmin -p MyPrinter -o Resolution=600dpi

Permission Issues

Check and fix permissions:

bash
# Add user to lpadmin group
sudo usermod -aG lpadmin username

# Fix CUPS directory permissions
sudo chmod -R 640 /etc/cups
sudo chown -R root:lpadmin /etc/cups

Summary

In this guide, you've learned how to:

Install and configure CUPS on Debian
Set up network access to your print server
Add and share printers
Configure client systems to use your print server
Manage print jobs and printer settings
Troubleshoot common printing issues

A properly configured Debian print server provides centralized printing services for your home or organization, making printer management more efficient and reducing costs.

Additional Resources

Practice Exercises

Set up a CUPS print server on a Debian virtual machine
Configure two virtual printers using the "CUPS-PDF" driver
Create different print queues with different settings
Configure automatic print job routing based on content type
Implement a basic print quota system for different users

If you spot any mistakes on this website, please let me know at [email protected]. I’d greatly appreciate your feedback! :)

Introduction​

Prerequisites​

Installing CUPS​

Configuring CUPS for Network Access​

Configuring Firewall (if applicable)​

Adding Printers to CUPS​

Using the Web Interface​

Using the Command Line​

Sharing Printers on the Network​

How Printing Works with CUPS​

Accessing the Print Server from Clients​

From Linux Clients​

From Windows Clients​

From macOS Clients​

Managing Print Jobs​

Setting Printer Defaults and Policies​

Print Quota Management​

Print Logs and Monitoring​

Backup and Restore CUPS Configuration​

Troubleshooting Common Issues​

Printer Not Detected​

Print Jobs Stuck in Queue​

Print Quality Issues​

Permission Issues​

Summary​

Additional Resources​

Practice Exercises​