Ubuntu VMs

This is a collection of Ubuntu VMs which are intended to be used with their cloud-init and cloud-localds scripts.

Dependencies

Arch Linux:

pacman -S cloud-init qemu-base

Ubuntu:

apt-get install cloud-init qemu-utils qemu-system-x86

For MacOS (with Homebrew) it's a little more complicated:

brew install qemu
brew install cdrtools
wget -O cloud-localds https://github.com/canonical/cloud-utils/raw/main/bin/cloud-localds
sed -i 's/genisoimage/mkisofs/g' cloud-localds
chmod +x cloud-localds

...Then put cloud-localds somewhere in your PATH.

In general, you just need the cloud-init scripts and Qemu.

How to Use

All top-level scripts take a distro (currently "ubuntu" or "centos") and a version (e.g. "18.04" or "7" or "8-stream") as arguments. Check setup.sh to see the URLs that it's downloading the images from. Submit a PR if you want to add more distros or URLs.

1. setup.sh will download an image from either the Ubuntu or CentOS images repositories and create all necessary images.
2. run.sh will run the given image.
3. reset.sh will "reset" an image; that is, the image will return to its pristine state and all files will be lost.

If you place files in data/, those files will be processed by config/create_user_data.sh. This script compresses and encodes each file and appends it to your cloud-init configuration, as a workaround to easily copy files into these VMs. These files will be placed in /home/ubuntu, but will be owned by root.

Examples

./setup.sh ubuntu 18.04
./run.sh ubuntu 18.04

If you want to erase all changes you've made to the Ubuntu 18.04 VM, do

./reset.sh ubuntu 18.04

You can replace "ubuntu" with "centos," and the scripts should support any of the versions available on either

https://cloud-images.ubuntu.com/releases/

or

https://cloud.centos.org/centos/

Details

The file user-data.yaml and metadata.yaml are files that are consumed by these scripts by passing an image containing them to qemu. You can create this image by doing:

cloud-localds seed.img user-data.yaml metadata.yaml

Next, download an .img file of the distro's distribution that you'd like to use. Let's call that disk.img.dist. Then, we can simply follow a typical qemu workflow:

Convert the compressed qcow file downloaded to a uncompressed qcow2:

qemu-img convert -O qcow2 disk.img.dist disk.img.orig

Resize the image to 52G from original image of 2G:

qemu-img resize disk.img.orig +50G

Create a delta disk to keep our .orig file pristine:

qemu-img create -f qcow2 -F qcow2 -b disk.img.orig disk.img.delta

Finally, run your qemu command.