ix.ai/docker-qemu

Notable features, beyond the automated build using GitLab CI:

Multi-arch build: linux/amd64, linux/arm64, linux/arm/v7, linux/386
Full support for RBD (CEPH) volumes - including libraries
Enabled rng-none
No additional signal patches needed, by using QMP to gracefully shut down the VM on container stop (with system_powerdown)

Supported tags

7.1
7.2, latest

The simple N.N.N tags refer to the QEMU versions.

Usage

This image is hosted on docker hub and gitlab registry:

ixdotai/qemu:latest
registry.gitlab.com/ix.ai/docker-qemu:latest

Examples

Create a new RBD volume:

sudo docker run --rm -it \
  -v /etc/ceph/ceph.conf:/etc/ceph/ceph.conf:ro \
  -v /etc/ceph/ceph.client.qemu.keyring:/etc/ceph/ceph.client.qemu.keyring:ro \
  --entrypoint "" \
  ixdotai/qemu:latest \
    qemu-img create -f raw rbd:rbd/desktop:id=qemu 100G

Start an image with an RBD volume, boot from the ISO:

sudo docker run --rm -it \
  --device /dev/kvm \
  -v /etc/ceph/ceph.conf:/etc/ceph/ceph.conf:ro \
  -v /etc/ceph/ceph.client.qemu.keyring:/etc/ceph/ceph.client.qemu.keyring:ro \
  -v /docker/mini.iso:/tmp/mini.iso \
  ixdotai/qemu:latest \
    -enable-kvm \
    -smp 4 \
    -m 8192 \
    -boot order=d \
    -device virtio-scsi-pci \
    -drive format=rbd,file=rbd:rbd/desktop:id=qemu,id=drive1,cache=writeback,if=none \
    -device driver=scsi-hd,drive=drive1,discard_granularity=512 \
    -netdev user,hostname=desktop,hostfwd=tcp::22-:22,id=net \
    -device virtio-net-pci,netdev=net \
    -serial stdio \
    -vnc :0 \
    -no-user-config \
    -cpu host \
    -nodefaults \
    -vga virtio \
    -cdrom /tmp/mini.iso

Global Variables

The following variables are supported for all operations type:

Variable	Default	Description
`QEMU_NO_QMP`	-	Set this to anything to disable the QMP Monitor and graceful shutdown handling
`QEMU_MONPORT`	`7100`	The port for the QMP Monitor
`QEMU_POWERDOWN_TIMEOUT`	`120`	After this many seconds, the VM gets killed after a graceful shutdown command
`QEMU_ARCH`	output of `uname -m`	Allows starting the VM with a different arch than the host. Supported: `i386`, `x86_64`, `aarch64`, `arm`, `mips64`, `mips64el`, `ppc64`, `sparc64`
`DEBUG_SCRIPT`	`false`	Set this to `true`, to have all de debug log of the script controlling the container. WARNING! This will generate a few log lines per second!

Tips

Variable inside the VMs

To add a string from outside the VM to be visible inside (for example, a host id), I'm using:

-smbios type=1,serial=alpine

I'm then reading this inside the VM with dmidecode --string system-serial-number

For more details, see this gist.

Mount a volume from the docker host inside the VM

This is only possible by exposing a FAT drive.

Let's say the volume on the docker host is /files.

You need to add the following to the docker run command:

  -v /files:/files:rw \

And in the VM command:

    -drive file=fat:rw:/folder,id=drive2,if=none,format=raw \
    -device driver=scsi-hd,drive=drive2 \

When you start your VM, you will see an additional drive - if you add it after the RBD one, it will be sdb in Linux.

Fork

This is a fork of tianon/docker-qemu.

Support for the original start-qemu script was still included at the time of the fork, from tianon/docker-qemu. If no arguments are passed to the image, then the environment variables documented in start-qemu are used.

Original README content below

tianon/qemu

touch /home/jsmith/hda.qcow2
docker run -it --rm \
	--device /dev/kvm \
	--name qemu-container \
	-v /home/jsmith/hda.qcow2:/tmp/hda.qcow2 \
	-e QEMU_HDA=/tmp/hda.qcow2 \
	-e QEMU_HDA_SIZE=100G \
	-e QEMU_CPU=4 \
	-e QEMU_RAM=4096 \
	-v /home/jsmith/downloads/debian.iso:/tmp/debian.iso:ro \
	-e QEMU_CDROM=/tmp/debian.iso \
	-e QEMU_BOOT='order=d' \
	-e QEMU_PORTS='2375 2376' \
	tianon/qemu

Note: port 22 will always be mapped (regardless of the contents of QEMU_PORTS).

For supplying additional arguments, use a command of start-qemu <args>. For example, to use -curses, one would docker run ... tianon/qemu start-qemu -curses.

For UEFI support, the ovmf package is installed, which can be utilized most easily by supplying --bios /usr/share/ovmf/OVMF.fd.

nxsre/docker-qemu