Containerization and Virtualization

This category covers container runtimes, container image tools, and other virtualization-related tools.

Container Runtimes

Podman

Podman is a modern, daemonless container engine that provides a Docker-compatible command-line interface, making it easy for users familiar with Docker to transition.

Installation

To install Podman, add the following line to configuration.nix:

virtualisation.podman.enable = true;

Verified Usage

podman run

podman run runs a command in a new container.

# Start a container, execute a command, and then exit
podman run --name=c1 docker.io/library/alpine ls /etc

# Start a container and attach to an interactive shell
podman run -it docker.io/library/alpine

podman image

podman image manages local images.

# List downloaded images
podman image ls

podman ps

podman ps lists containers.

# Show the status of all containers (including exited ones)
podman ps -a

podman rm

podman rm removes one or more containers.

# Remove a container named foo
podman rm foo

Container Image Tools

Skopeo

Skopeo inspects and copies container images without a daemon.

Installation

environment.systemPackages = [ pkgs.skopeo ];

Verified Usage

# Inspect a remote image
skopeo inspect docker://docker.io/library/alpine:latest

# List all tags for a repository
skopeo list-tags docker://docker.io/library/alpine

Virtualization

QEMU

QEMU is the most widely used open-source machine emulator and virtualizer. It supports full system emulation as well as user-mode binary translation.

Asterinas does not yet support hardware-assisted virtualization (KVM), therefore QEMU runs exclusively with TCG (Tiny Code Generator / software emulation) on Asterinas NixOS.

Installation

environment.systemPackages = with pkgs; [ qemu_kvm ];

environment.variables = {
  LINUX_BZIMAGE = "${pkgs.linuxPackages.kernel}/bzImage";
  OVMF_PATH = "${pkgs.OVMF.fd}/FV/OVMF.fd";
};

Environment Variables

The following environment variables are automatically provided when building the NixOS test suite:

• LINUX_BZIMAGE: Path to the standard Linux kernel bzImage
• OVMF_PATH: Path to the OVMF (UEFI) firmware

You can enable them by building with:

make nixos NIXOS_TEST_SUITE=containerization-and-virtualization

Verified Usage

Display QEMU version

qemu-system-$(uname -m) --version

Run Linux kernel with TCG

qemu-system-$(uname -m) \
  -accel tcg \
  -kernel $LINUX_BZIMAGE \
  -initrd /run/current-system/initrd \
  -nographic -no-reboot \
  -append 'console=ttyS0 panic=-1 rdinit=/bin/init'

Run Asterinas kernel with TCG

qemu-system-$(uname -m) \
  -accel tcg \
  -cpu Icelake-Server \
  -machine q35 -m 1G \
  -bios $OVMF_PATH \
  -kernel /run/current-system/kernel \
  -initrd /run/current-system/initrd \
  -device isa-debug-exit,iobase=0xf4,iosize=0x04 \
  -nographic -no-reboot \
  -append 'console=ttyS0 panic=-1 init=/bin/init'

Note: Running the Asterinas kernel requires the linux/multiboot boot protocol (multiboot2 is not supported). Compile Asterinas with:

make nixos BOOT_PROTOCOL=linux NIXOS_TEST_SUITE=containerization-and-virtualization