108.4 Manage Printers and Printing

Introduction

This lesson is about printing on Linux without turning it into a full printer-admin course.

The main question is:

How do you understand printer queues, inspect jobs, and use basic CUPS and LPD-compatible printing commands?

What you should be able to do after this lesson:

• Understand the role of CUPS.
• Recognize the idea of a print queue.
• Submit, inspect, and remove print jobs.
• Know the classic commands lpr, lpq, and lprm.
• Understand the difference between local and remote printers.

Big Idea: Printing Is Mostly Queue Management

Beginners often imagine printing as a single direct action. In Linux, it is usually better to think like this:

user sends a job -> the job enters a queue -> the print service hands it to a printer

That is why so many printing commands are about:

• checking queues
• listing printers
• canceling stuck jobs
• looking at service status

CUPS

Most Linux printing today uses CUPS:

Common UNIX Printing System

Its job is to:

• manage printers
• accept print jobs
• keep track of queues
• talk to local or remote printers

Common configuration directory:

/etc/cups/

You do not need deep CUPS administration for LPIC-1. You do need to understand the basic workflow.

Printers and Queues

A printer queue is the waiting line of jobs for a printer.

That means you should be able to answer:

• What printers are available?
• Is my job waiting?
• Is the printer paused or stopped?
• Can I remove a stuck job?

Useful commands on many systems:

lpstat -p -d
lpstat -t

Submitting a Job

Classic command:

lpr file.txt

This sends a print job to the default printer.

If you want a specific printer:

lpr -P printer_name file.txt

You do not need to memorize every option. The important thing is understanding that lpr submits a job into a queue.

Inspecting the Queue

Classic command:

lpq

This shows jobs currently waiting in the printer queue.

Many systems also support:

lpstat -o

That is useful when a user says:

• "I printed something but nothing happened."

Often the job is simply still queued, blocked, or paused.

Removing a Job

Classic command:

lprm <job_id>

Some systems also support:

cancel <job_id>

The key beginner idea:

• if a job is stuck, remove it from the queue first
• then test printing again with a simple text file

Local vs Remote Printers

Linux can print to:

• a printer attached directly to the machine
• a network printer
• a printer shared by another host

At LPIC-1 level, you just need to understand that CUPS can manage both local and remote printers.

Basic Troubleshooting

When printing fails, check in this order:

1. is the CUPS service running?
2. does Linux know about the printer?
3. is the job in the queue?
4. is the printer paused or stopped?
5. can you print a very small plain text file?

That simple order solves many beginner problems.

Practice Step by Step

1) Inspect printers and the default destination

1. Run: lpstat -p -d
2. If there is no printer configured, note that this is also useful information.
3. Then run: lpstat -t
4. Look for printer status and queue information.

2) Submit a tiny text job

1. Create a small file: printf 'Linux printing practice\n' > /tmp/print-test.txt
2. If a printer is configured, send it: lpr /tmp/print-test.txt
3. Check the queue: lpq

3) Remove a queued job

1. Check the queue: lpq
2. If a test job is listed, remove it: lprm <job_id>
3. Check again: lpq

Cheat Sheet

lpstat -p -d
lpstat -t
lpr file.txt
lpr -P printer_name file.txt
lpq
lprm <job_id>
cancel <job_id>
systemctl status cups
ls /etc/cups/

Legacy / Exam Note

LPIC still mentions the LPD-compatible commands lpr, lpq, and lprm. Modern Linux printing usually sits on top of CUPS, but those older-style commands are still worth recognizing for the exam and for troubleshooting.