qemu-docker

This repository contains a Docker container for running x86_64 virtual machines using QEMU. It uses high-performance QEMU options (KVM, and TAP network driver).

Docker Hub: jkz0/qemu

Using the container

Via docker run:

$ docker run --rm -it \
    --device=/dev/kvm:/dev/kvm --device=/dev/net/tun:/dev/net/tun \
    --cap-add NET_ADMIN -v $VM_IMAGE_FILE:/image \
    jkz0/qemu:latest

Via docker-compose.yml:

version: "3"
services:
    vm:
        image: jkz0/qemu:latest
        cap_add:
            - NET_ADMIN
        devices:
            - /dev/net/tun
            - /dev/kvm
        volumes:
            - ${VM_IMAGE:?VM image must be supplied}:/image
        restart: always

Tips

• VM networking is configured via DHCP, make sure to enable DHCP in your VM image. VMs will use the IP address of the container.
• You can quit the VM (when attached to the container) by entering the special key sequence C-a x. Killing the docker container will also shut down the VM.

Caveat Emptor

• Only x86_64 supported new. PRs to support other architectures welcome, though I imagine 99% of use-cases will be x86_64.
• VMs will not be able to resolve container-names on user-defined bridges. This is due to the way Docker's "Embedded DNS" server works. VMs can still connect to other containers on the same bridge using IP addresses.