Build virtual machine image from Docker images
The project is heavily inspired by the article and the work done by iximiuz on docker-to-linux.
Many thanks to him.
Status: alpha
Only Linux is supported.
If you want to run it on OSX or Windows (the last one is totally untested) you can do it using Docker:
alias d2vm='docker run --rm -i -t --privileged -v /var/run/docker.sock:/var/run/docker.sock -v $PWD:/build -w /build linkacloud/d2vm'
Working and tested:
- Ubuntu
- Debian
- Alpine
Need fix:
- CentOS
Unsupported:
- RHEL
The program use the /etc/os-release
file to discover the Linux distribution and install the Kernel,
if the file is missing, the build cannot succeed.
Obviously, Distroless images are not supported.
Clone the git repository:
git clone https://github.com/linka-cloud/d2vm && cd d2vm
Install using the Go tool chain:
go install ./cmd/d2vm
which d2vm
# Should be install in the $GOBIN directory
/go/bin/d2vm
Or use an alias to the docker image:
alias d2vm='docker run --rm -i -t --privileged -v /var/run/docker.sock:/var/run/docker.sock -v $PWD:/build -w /build linkacloud/d2vm'
which d2vm
d2vm: aliased to docker run --rm -i -t --privileged -v /var/run/docker.sock:/var/run/docker.sock -v $PWD:/build -w /build linkacloud/d2vm
b2vm convert --help
Convert Docker image to vm image
Usage:
d2vm convert [docker image] [flags]
Flags:
-d, --debug Enable Debug output
-f, --force Override output qcow2 image
-h, --help help for convert
-o, --output string The output image (default "disk0.qcow2")
-O, --output-format string The output image format, supported formats: qcow2 qed raw vdi vhd vmdk (default "qcow2")
-p, --password string The Root user password (default "root")
--pull Always pull docker image
-s, --size string The output image size (default "10G")
Create an image based on the ubuntu official image:
sudo d2vm convert ubuntu -o ubuntu.qcow2 -p MyP4Ssw0rd
INFO[0000] pulling image ubuntu
INFO[0001] inspecting image ubuntu
INFO[0002] docker image based on Ubuntu
INFO[0002] building kernel enabled image
INFO[0038] creating root file system archive
INFO[0040] creating vm image
INFO[0040] creating raw image
INFO[0040] mounting raw image
INFO[0040] creating raw image file system
INFO[0040] copying rootfs to raw image
INFO[0041] setting up rootfs
INFO[0041] installing linux kernel
INFO[0042] unmounting raw image
INFO[0042] writing MBR
INFO[0042] converting to qcow2
You can now run your ubuntu image using the created ubuntu.qcow2
image with qemu:
./qemu.sh ununtu.qcow2
SeaBIOS (version 1.13.0-1ubuntu1.1)
iPXE (http://ipxe.org) 00:03.0 CA00 PCI2.10 PnP PMM+BFF8C920+BFECC920 CA00
Booting from Hard Disk...
SYSLINUX 6.04 EDD 20191223 Copyright (C) 1994-2015 H. Peter Anvin et al
Now booting the kernel from SYSLINUX...
Loading /boot/vmlinuz... ok
Loading /boot/initrd.img...ok
[ 0.000000] Linux version 5.4.0-109-generic (buildd@ubuntu) (gcc version 9)
[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz ro root=UUID=b117d206-b8
[ 0.000000] KERNEL supported cpus:
[ 0.000000] Intel GenuineIntel
[ 0.000000] AMD AuthenticAMD
[ 0.000000] Hygon HygonGenuine
[ 0.000000] Centaur CentaurHauls
[ 0.000000] zhaoxin Shanghai
...
Welcome to Ubuntu 20.04.4 LTS!
[ 3.610631] systemd[1]: Set hostname to <localhost>.
[ 3.838984] systemd[1]: Created slice system-getty.slice.
[ OK ] Created slice system-getty.slice.
[ 3.845038] systemd[1]: Created slice system-modprobe.slice.
[ OK ] Created slice system-modprobe.slice.
[ 3.852054] systemd[1]: Created slice system-serial\x2dgetty.slice.
[ OK ] Created slice system-serial\x2dgetty.slice.
...
Ubuntu 20.04.4 LTS localhost ttyS0
localhost login:
Log in using the root user and the password configured at build time.
localhost login: root
Password:
Welcome to Ubuntu 20.04.4 LTS (GNU/Linux 5.4.0-109-generic x86_64)
* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage
This system has been minimized by removing packages and content that are
not required on a system that users do not log into.
To restore this content, you can run the 'unminimize' command.
The programs included with the Ubuntu system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.
Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.
root@localhost:~#
Type poweroff
to shutdown the vm.
The example directory contains very minimalistic examples:
cd examples
ubuntu.Dockerfile :
FROM ubuntu
RUN apt update && apt install -y openssh-server && \
echo "PermitRootLogin yes" >> /etc/ssh/sshd_config \
When building the vm image, d2vm will create a root password, so there is no need to configure it now.
Build the vm image:
The build command take most of its flags and arguments from the docker build command.
d2vm build --help
Build a vm image from Dockerfile
Usage:
d2vm build [context directory] [flags]
Flags:
--build-arg stringArray Set build-time variables
-d, --debug Enable Debug output
-f, --file string Name of the Dockerfile (Default is 'PATH/Dockerfile') (default "Dockerfile")
--force Override output image
-h, --help help for build
-o, --output string The output image (default "disk0.qcow2")
-O, --output-format string The output image format, supported formats: qcow2 qed raw vdi vhd vmdk (default "qcow2")
-p, --password string Root user password (default "root")
-s, --size string The output image size (default "10G")
sudo d2vm build -p MyP4Ssw0rd -f ubuntu.Dockerfile -o ubuntu.qcow2 .
Or if you want to create a VirtualBox image:
sudo d2vm build -p MyP4Ssw0rd -f ubuntu.Dockerfile -O vdi -o ubuntu.vdi .
A complete example setting up a ZSH workstation is available in the examples/full directory.
You can find the Dockerfiles used to install the Kernel in the templates directory.
- Create service from
ENTRYPOINT
CMD
WORKDIR
andENV
instructions ? - Inject Image
ENV
variables into.bashrc
or other service environment file ? - Use image layers to create rootfs instead of container ?