Docker container for running virtual machines using QEMU.
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Web-based viewer to control the machine directly from your browser
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Supports
.iso,.img,.qcow2,.vhd,.vhdx,.vdi,.vmdkand.rawdisk formats -
High-performance options (like KVM acceleration, kernel-mode networking, IO threading, etc.) to achieve near-native speed
Via Docker Compose:
services:
qemu:
container_name: qemu
image: qemux/qemu-docker
environment:
BOOT: "https://dl-cdn.alpinelinux.org/alpine/v3.19/releases/x86_64/alpine-virt-3.19.1-x86_64.iso"
devices:
- /dev/kvm
cap_add:
- NET_ADMIN
ports:
- 8006:8006
stop_grace_period: 2mVia Docker CLI:
docker run -it --rm -e "BOOT=http://example.com/image.iso" -p 8006:8006 --device=/dev/kvm --cap-add NET_ADMIN qemux/qemu-dockerVia Kubernetes:
kubectl apply -f kubernetes.ymlVery simple! These are the steps:
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Set the
BOOTenvironment variable to the URL of any disk image you want to install. -
Start the container and connect to port 8006 using your web browser.
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You will see the screen and can now install the OS of your choice using your keyboard and mouse.
Enjoy your brand new machine, and don't forget to star this repo!
To change the storage location, include the following bind mount in your compose file:
volumes:
- /var/qemu:/storageReplace the example path /var/qemu with the desired storage folder.
To expand the default size of 16 GB, add the DISK_SIZE setting to your compose file and set it to your preferred capacity:
environment:
DISK_SIZE: "128G"Tip
This can also be used to resize the existing disk to a larger capacity without any data loss.
You can use a local image file directly, and skip the download altogether, by binding it in your compose file:
volumes:
- /home/user/example.iso:/boot.isoThis way you can supply a boot.iso, boot.img or boot.qcow2 file.
Note
The URL of the BOOT variable will be ignored in this case.
You can use qemu-arm to run ARM64-based images.
Use dockur/windows instead, as it includes all the drivers required during installation, amongst many other features.
Use dockur/macos instead, as it uses all the right settings and automaticly downloads the installation files.
By default, the machine makes use of virtio-scsi drives for performance reasons, and even though most Linux kernels bundle the necessary driver for this device, that may not always be the case for other operating systems.
If your machine fails to detect the hard drive, you can modify your compose file to use virtio-blk instead:
environment:
DISK_TYPE: "blk"Tip
If it still fails to boot, you can set the value to ide to emulate a IDE drive, which is slow but requires no drivers and is compatible with almost every system.
By default, the container will be allowed to use a maximum of 1 CPU core and 1 GB of RAM.
If you want to adjust this, you can specify the desired amount using the following environment variables:
environment:
RAM_SIZE: "4G"
CPU_CORES: "4"To verify that your system supports KVM, run the following commands:
sudo apt install cpu-checker
sudo kvm-okIf you receive an error from kvm-ok indicating that KVM acceleration can't be used, please check whether:
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the virtualization extensions (
Intel VT-xorAMD SVM) are enabled in your BIOS. -
you are running an operating system that supports them, like Linux or Windows 11 (macOS and Windows 10 do not unfortunately).
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you enabled "nested virtualization" if you are running the container inside a virtual machine.
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you are not using a cloud provider, as most of them do not allow nested virtualization for their VPS's.
If you didn't receive any error from kvm-ok at all, but the container still complains that /dev/kvm is missing, it might help to add privileged: true to your compose file (or --privileged to your run command), to rule out any permission issue.
By default, the container uses bridge networking, which shares the IP address with the host.
If you want to assign an individual IP address to the container, you can create a macvlan network as follows:
docker network create -d macvlan \
--subnet=192.168.0.0/24 \
--gateway=192.168.0.1 \
--ip-range=192.168.0.100/28 \
-o parent=eth0 vlanBe sure to modify these values to match your local subnet.
Once you have created the network, change your compose file to look as follows:
services:
qemu:
container_name: qemu
..<snip>..
networks:
vlan:
ipv4_address: 192.168.0.100
networks:
vlan:
external: trueAn added benefit of this approach is that you won't have to perform any port mapping anymore, since all ports will be exposed by default.
Important
This IP address won't be accessible from the Docker host due to the design of macvlan, which doesn't permit communication between the two. If this is a concern, you need to create a second macvlan as a workaround.
After configuring the container for macvlan, it is possible for the VM to become part of your home network by requesting an IP from your router, just like a real PC.
To enable this mode, add the following lines to your compose file:
environment:
DHCP: "Y"
devices:
- /dev/vhost-net
device_cgroup_rules:
- 'c *:* rwm'Note
In this mode, the container and the VM will each have their own separate IPs.
To create additional disks, modify your compose file like this:
environment:
DISK2_SIZE: "32G"
DISK3_SIZE: "64G"
volumes:
- /home/example:/storage2
- /mnt/data/example:/storage3It is possible to pass-through disk devices directly by adding them to your compose file in this way:
devices:
- /dev/sdb:/disk1
- /dev/sdc:/disk2Use /disk1 if you want it to become your main drive, and use /disk2 and higher to add them as secondary drives.
To pass-through a USB device, first lookup its vendor and product id via the lsusb command, then add them to your compose file like this:
environment:
ARGUMENTS: "-device usb-host,vendorid=0x1234,productid=0x1234"
devices:
- /dev/bus/usbYou can create the ARGUMENTS environment variable to provide additional arguments to QEMU at runtime:
environment:
ARGUMENTS: "-device usb-tablet"The BOOT URL accepts files in any of the following formats:
| Extension | Format |
|---|---|
.img |
Raw |
.raw |
Raw |
.iso |
Optical |
.qcow2 |
QEMU |
.vmdk |
VMware |
.vhd |
VirtualPC |
.vhdx |
Hyper-V |
.vdi |
VirtualBox |
Tip
It will also accept .img.gz, .qcow2.xz, .iso.zip and many more, as it automaticly extracts compressed files.