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LXC & LXD

2 min read

LXC (Linux Containers)

  • Low-level container technology (like chroot on steroids).

  • Gives you lightweight, OS-level virtualization.

  • Each container shares the host kernel but feels like a separate Linux system.

  • Used by developers and sysadmins for isolated environments.

LXD

  • High-level manager for LXC.

  • Adds easier commands, image management, networking, snapshots, profiles, etc.

  • Makes LXC containers usable like lightweight VMs.

Think of:
LXC = engine
LXD = friendly dashboard + tools on top

🔧 How Does It Work?

  • Containers run isolated processes with their own filesystem, network, users, and optionally IP addresses.

  • Host kernel is shared, but containers think they’re full systems.

  • No hardware emulation, so it’s fast and efficient — perfect for RPi.

⚙️ LXD System Structure

  • Containers: lightweight full Linux systems (Ubuntu, Debian, etc.)

  • Images: base OS templates (from https://images.linuxcontainers.org/)

  • Storage Pools: where containers live (e.g., dir, zfs)

  • Networks: bridge for containers (usually lxdbr0)

  • Profiles: reusable configs (network, storage, etc.)

📥 Installation (on Raspberry Pi OS or Debian-based systems)

sudo apt install snapd 
sudo snap install lxd 
sudo lxd init

✅ Initial Setup (lxd init)

Key prompts:

  • Storage backend: use dir (simple)

  • Network bridge: usually lxdbr0 (isolates containers, gives NAT internet access)

  • Remote images: yes

  • IPv6: your choice (you can say no)

🔑 Common LXD Commands

🔹 Images

lxc image list ubuntu:       # See available OS images
lxc launch images:ubuntu/22.04 mycontainer

To start your first container, try: lxc launch ubuntu:22.04 Or for a virtual machine: lxc launch ubuntu:22.04 —vm

🔹 Container Management

lxc list                     # Show running containers
lxc launch ubuntu:22.04 lab1  # Create and start a container
lxc exec lab1 -- bash         # Shell into container
lxc stop lab1
lxc start lab1
lxc delete lab1

🔹 Snapshot & Restore

lxc snapshot lab1 clean
lxc restore lab1 clean

🔹 Filesystem

lxc file push file.txt lab1/tmp/   # Upload
lxc file pull lab1/tmp/file.txt .  # Download

🔹 Network

lxc network list
lxc network show lxdbr0

🔹 Profiles

lxc profile list
lxc profile show default

🔹 Locations

/var/lib/lxd/

🔑 Common LXC Commands

To install a specific distro:

  1. Check https://images.linuxcontainers.org to specify
  2. Run sudo apt install lxc-templates
  3. Run sudo lxc-create -n name -t download
  4. Answer the questions (fedora, 42, arm64)

To remove lxc container:

sudo lxc-destroy -n lxc-fedora

List lxc containers

lxs-ls

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