Incus vs. Docker: The Next-Generation Guide to System Containers

Incus vs. Docker: The Next-Generation Guide to System Containers

In the world of containerization, Docker has long been the household name. However, for developers who need more than just a place to run a single process, Incus has emerged as the premier community-driven alternative.

While Docker focuses on Application Containers (packaging a single app), Incus focuses on System Containers (packaging a full Linux OS). Think of Incus as a way to create “instant Virtual Machines” that run at the speed of a container.

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🚀 Key Differences at a Glance

Feature	Docker	Incus
Philosophy	“One process per container”	“One full OS per container”
Primary Use	Microservices, CI/CD, Deployment	Development Labs, AI Sandboxing, VPS replacement
Init System	No (Usually just entrypoint)	Yes (systemd, OpenRC work natively)
Security	Process-level isolation	Unprivileged containers by default + VM support
Persistence	Volatile (requires Volumes/Bind mounts)	Persistent (acts like a physical disk)
Hardware	Hard to pass through GPUs/USB	Native, low-latency device passthrough

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⌨️ Command Comparison: Speaking the Language

If you already know Docker, learning Incus is a matter of mapping your existing knowledge to a new set of verbs.

Action	Docker Command	Incus Command
Start a container	docker run -d --name web ubuntu	incus launch images:ubuntu/24.04 web
List containers	docker ps	incus list
Access shell	docker exec -it web bash	incus shell web
Stop container	docker stop web	incus stop web
Remove container	docker rm -f web	incus delete -f web
Create Image	docker commit web my-image	incus publish web --alias my-image
View Logs	docker logs web	incus info --show-log web
Copy Files	docker cp file web:/path	incus file push file web/path

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🛠️ Setting Up Your Incus Environment (Ubuntu 24.04+)

Incus is now officially supported in the latest Ubuntu repositories, making installation a breeze.

1. Installation & Init

# Install the core packages
sudo apt update && sudo apt install -y incus

# Add your user to the management group
sudo usermod -aG incus-admin $USER
newgrp incus-admin

# Initialize the system (Interactive Wizard)
incus admin init

Tip: During init, choosing ZFS or Btrfs for storage allows for near-instant snapshots.

2. Launching your first “Dev Box”

Unlike Docker Hub, Incus uses multiple “remotes.” The most common is the community-maintained images: server.

# Launch a persistent Ubuntu 24.04 container
incus launch images:ubuntu/24.04 dev-box

# Launch a MicroVM (for AI sandboxing or extra security)
incus launch images:ubuntu/24.04 ai-box --vm

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🤖 Advanced Management: The “Pro” Workflow

Using Profiles for Automation

Instead of manual configuration, you can use Profiles to apply settings (like GPU access or mounted folders) to many containers at once.

# Create a profile for Rails development
incus profile create rails-dev

# Add a device to map your code folder from the host
incus profile device add rails-dev my-code disk \
    source=/home/user/projects/app \
    path=/root/app

# Apply this profile to your container
incus profile add dev-box rails-dev

Snapshotting (The “Undo” Button)

This is where Incus shines over Docker for development. Before making a big change:

# Create a snapshot
incus snapshot create dev-box pre-upgrade

# Messed up? Restore instantly
incus restore dev-box pre-upgrade

Running Docker inside Incus

Yes, you can have the best of both worlds. To run Docker inside an Incus container (nesting):

incus config set dev-box security.nesting=true
incus restart dev-box
# Now install docker inside the dev-box as usual!

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🎯 Conclusion

Use Docker when you have a finished app that you want to ship to the cloud. Use Incus when you are building that app. It provides a stable, persistent, and high-performance environment that handles system services and hardware with ease—all while keeping your host machine clean and organized.