Linux: Snap Package Management

Snaps are Linux app packages for desktop, cloud, and IoT that are self-contained, simple to install, secure, cross-platform, and dependency-free. This guide covers everything you need to know about using Snap packages.

Note

Official Resources:

What is Snap?

Snaps are containerized software packages that work across different Linux distributions. They bundle all dependencies, ensuring applications run consistently regardless of the underlying system.

Benefits of Snap

Self-contained: All dependencies bundled together
Simple to install: One command installation
Secure: Isolated from the rest of the system
Cross-platform: Works on multiple Linux distributions
Dependency-free: No dependency conflicts
Automatic updates: Background updates by default
Easy rollback: Revert to previous versions easily

Installing Snap on Linux Mint

Linux Mint blocks snap by default. Follow these steps to enable snap support.

Important

Reference: Installing Snap on Linux Mint

Step 1: Remove nosnap.pref File

Move the nosnap.pref file that blocks snap installation:

sudo mv /etc/apt/preferences.d/nosnap.pref ~/Documents/nosnap.backup

This moves the file to your Documents folder as a backup.

Step 2: Update Package Database

Update the package list:

sudo apt update

Step 3: Install snapd

Install the snap daemon:

sudo apt install snapd

Step 4: Verify Installation

Check snap version to verify successful installation:

snap --version

Troubleshooting Installation

If you encounter errors during installation, refer to this solution:

Fig. 34 Snap installation error example

Installing Snap on Other Linux Distributions

Ubuntu

Snap comes pre-installed on Ubuntu 16.04 and later. If not installed:

sudo apt update
sudo apt install snapd

Debian

sudo apt update
sudo apt install snapd
sudo snap install core

Fedora

sudo dnf install snapd

Arch Linux

git clone https://aur.archlinux.org/snapd.git
cd snapd
makepkg -si

Installing Applications with Snap

Basic Installation Syntax

sudo snap install <package-name>

Common Applications

Communication Tools

Install Slack:

sudo snap install slack

Install Microsoft Teams:

sudo snap install teams-for-linux

Development Tools

Install Postman:

sudo snap install postman

Install PHPStorm:

sudo snap install phpstorm --classic

Install VS Code:

sudo snap install code --classic

Browsers

Install Brave Browser:

sudo snap install brave

Install Chromium:

sudo snap install chromium

Utilities

Install Snap Store (GUI for managing snaps):

sudo snap install snap-store

Install VLC Media Player:

sudo snap install vlc

Install GIMP:

sudo snap install gimp

Installing with Different Confinement Modes

Snap packages can have different confinement levels:

Classic Confinement (full system access):

sudo snap install <package-name> --classic

Example:

sudo snap install phpstorm --classic

Strict Confinement (default, sandboxed):

sudo snap install <package-name>

Devmode (for testing, reduced security):

sudo snap install <package-name> --devmode

Snap Commands Reference

Checking Version

Check installed snap version:

snap --version

Searching for Packages

Search by name or description:

snap find <search-term>

Examples:

snap find "media player"
snap find editor
snap find browser

Search for specific package:

snap info <package-name>

Example:

snap info vlc

Listing Installed Snaps

List all installed snaps:

snap list

List all revisions (including disabled):

snap list --all

Output includes:

Name
Version
Revision number
Tracking channel
Publisher
Notes

Installing Packages

Install from stable channel (default):

sudo snap install <package-name>

Install from specific channel:

sudo snap install <package-name> --channel=<channel>

Channels: stable, candidate, beta, edge

Example:

sudo snap install vlc --channel=edge

Install specific revision:

sudo snap install <package-name> --revision=<number>

Updating Packages

Update all installed snaps:

sudo snap refresh

Update specific snap:

sudo snap refresh <package-name>

Example:

sudo snap refresh teams-for-linux

Check for available updates:

snap refresh --list

Removing Packages

Remove a snap package:

sudo snap remove <package-name>

Example:

sudo snap remove slack

Remove snap and purge data:

sudo snap remove <package-name> --purge

Reverting to Previous Version

Revert to previous revision:

sudo snap revert <package-name>

Example:

sudo snap revert firefox

Managing Snap Services

List services:

snap services

Start a service:

sudo snap start <package-name>.<service-name>

Stop a service:

sudo snap stop <package-name>.<service-name>

Restart a service:

sudo snap restart <package-name>.<service-name>

Viewing Snap Information

View detailed package information:

snap info <package-name>

View snap changes (history):

snap changes

View specific change details:

snap change <change-id>

Cleaning Up Old Snap Revisions

Snap keeps old revisions for rollback purposes. Over time, these can consume disk space.

Understanding Snap Revisions

By default, Snap keeps 3 revisions of each package:

Current active revision
Previous 2 revisions for rollback

Manual Cleanup

List all revisions including disabled ones:

snap list --all

Remove specific revision:

sudo snap remove <package-name> --revision=<revision-number>

Example:

sudo snap remove firefox --revision=1234

Automated Cleanup Script

Create a script to automatically clean old snap revisions.

Important

Reference: Cleanup Snaps Guide

Step 1: Create the Cleanup Script

Create a file named clean-snap.sh:

nano clean-snap.sh

Step 2: Add Script Content

Add the following content to the file:

#!/bin/bash

echo "Removes old revisions of snaps"
echo  # Adds a line break

set -eu

snap list --all | awk '/disabled/{print $1, $3}' |

    while read snapname revision; do
        echo "Removing $snapname revision $revision"
        sudo snap remove "$snapname" --revision="$revision"
        echo
    done

Step 3: Make Script Executable

Grant execute permission:

sudo chmod u+x clean-snap.sh

Step 4: Move Script to System Path

Move the script for global access:

sudo mv clean-snap.sh /usr/bin/clean_snaps

Step 5: Run the Cleanup

Execute the cleanup command:

clean_snaps

Clean snaps command output — Fig. 35 Clean snaps command execution result

Script Explanation

The script:

Lists all snap packages including disabled revisions
Filters only disabled revisions using awk
Iterates through each disabled revision
Removes each old revision
Displays progress as it removes packages

Schedule Automatic Cleanup

To run cleanup automatically, add to cron:

sudo crontab -e

Add this line to run monthly:

0 0 1 * * /usr/bin/clean_snaps

Advanced Snap Management

Snap Configuration

Set snap configuration:

sudo snap set <package-name> <key>=<value>

Get snap configuration:

snap get <package-name> <key>

View all configuration:

snap get <package-name>

Snap Connections

Snaps use interfaces to access system resources.

List available interfaces:

snap interface

List connections:

snap connections

Connect an interface:

sudo snap connect <snap>:<interface> <slot>

Disconnect an interface:

sudo snap disconnect <snap>:<interface>

Snap Aliases

Create shortcuts for snap commands:

sudo snap alias <package-name>.<command> <alias-name>

Example:

sudo snap alias postman.postman pm

Remove alias:

sudo snap unalias <alias-name>

Controlling Snap Updates

Hold updates for specific snap:

sudo snap refresh --hold=<duration> <package-name>

Example (hold for 90 days):

sudo snap refresh --hold=90d firefox

Unhold updates:

sudo snap refresh --unhold <package-name>

Disable automatic updates globally (not recommended):

sudo snap set system refresh.retain=2

Checking Disk Usage

View disk space used by snaps:

du -sh /var/lib/snapd/snaps

View space per snap:

du -h /var/lib/snapd/snaps/* | sort -h

Best Practices

Regular Updates

Keep snaps updated for security and features:
```
sudo snap refresh
```
Cleanup Old Revisions

Run cleanup script monthly to free disk space.
Use Classic Confinement Wisely

Only use --classic when necessary, as it reduces security.
Monitor Disk Usage

Check snap disk usage regularly, especially on systems with limited storage.
Check Reviews

Before installing, check snap info and reviews:
```
snap info <package-name>
```
Use Official Snaps

Install snaps from verified publishers when possible.
Test Before Production

Test snaps in development environment before deploying to production.
Keep Backups

Snap data is stored separately; ensure you backup:
```
~/snap/<package-name>/
```

Troubleshooting

Snap Not Found

If snap command is not found after installation:

export PATH=$PATH:/snap/bin
echo 'export PATH=$PATH:/snap/bin' >> ~/.bashrc
source ~/.bashrc

Permission Denied

If you get permission errors:

sudo snap install <package-name>

Some snaps require specific permissions through interfaces.

Application Won’t Start

Check snap logs:

snap logs <package-name>

Check if service is running:

snap services <package-name>

Try restarting the snap:

sudo snap restart <package-name>

Disk Space Issues

If snaps consume too much space:

Run cleanup script to remove old revisions
Remove unused snaps:
```
sudo snap remove <package-name>
```
Change retention policy:
```
sudo snap set system refresh.retain=2
```

Update Failed

If update fails:

sudo snap refresh <package-name> --ignore-validation

Or try:

sudo snap revert <package-name>

Quick Reference

Table 5 Essential Snap Commands
Command	Description
`snap find <term>`	Search for packages
`snap info <package>`	Show package details
`snap list`	List installed snaps
`snap list --all`	List all revisions
`sudo snap install <package>`	Install a snap
`sudo snap install <package> --classic`	Install with classic confinement
`sudo snap refresh`	Update all snaps
`sudo snap refresh <package>`	Update specific snap
`sudo snap remove <package>`	Remove a snap
`sudo snap revert <package>`	Revert to previous version
`snap changes`	View installation history
`snap services`	List snap services
`snap connections`	View interface connections
`clean_snaps`	Clean old revisions (custom script)

Common Applications to Install

Table 6 Popular Snap Packages
Category	Application	Install Command
Development	VS Code	`snap install code --classic`
	PHPStorm	`snap install phpstorm --classic`
	Postman	`snap install postman`
	Docker	`snap install docker`
Communication	Slack	`snap install slack`
	Skype	`snap install skype`
	Teams	`snap install teams-for-linux`
	Discord	`snap install discord`
Browsers	Brave	`snap install brave`
	Chromium	`snap install chromium`
	Firefox	`snap install firefox`
Multimedia	VLC	`snap install vlc`
	Spotify	`snap install spotify`
	OBS Studio	`snap install obs-studio`
Graphics	GIMP	`snap install gimp`
	Inkscape	`snap install inkscape`
Utilities	Snap Store	`snap install snap-store`

Conclusion

Snap packages provide a universal, secure, and easy way to install and manage applications on Linux. With automatic updates, easy rollbacks, and cross-distribution compatibility, Snaps simplify software management for both users and developers.

Tip

Start with popular applications like Slack, VS Code, or Brave to get familiar with Snap before installing critical development tools.