Autoinstall Quick Start

The intent of this page is to provide simple instructions to perform an autoinstall in a VM on your machine.

This page assumes you are on the amd64 architecture. There is a version for s390x too.

Providing the autoinstall data over the network

This method is the one that generalizes most easily to doing an entirely network based install, where a machine netboots and then is automatically installed.

Download the ISO

cd ~/Downloads
wget http://releases.ubuntu.com/20.04/ubuntu-20.04-live-server-amd64.iso

Mount the ISO

sudo mount -r ~/Downloads/ubuntu-20.04-live-server-amd64.iso /mnt

Write your autoinstall config

This means creating cloud-init config as follows:

mkdir -p ~/www
cd ~/www
cat > user-data << 'EOF'
#cloud-config
autoinstall:
  version: 1
  identity:
    hostname: ubuntu-server
    password: "$6$exDY1mhS4KUYCE/2$zmn9ToZwTKLhCw.b4/b.ZRTIZM30JZ4QrOQ2aOXJ8yk96xpcCof0kxKwuX1kqLG/ygbJ1f8wxED22bTL4F46P0"
    username: ubuntu
EOF
touch meta-data

The crypted password is just “ubuntu”.

Serve the cloud-init config over http

Leave this running in one terminal window:

cd ~/www
python3 -m http.server 3003

Create a target disk

truncate -s 10G image.img

Run the install!

kvm -no-reboot -m 1024 \
    -drive file=image.img,format=raw,cache=none,if=virtio \
    -cdrom ~/Downloads/ubuntu-20.04-live-server-amd64.iso \
    -kernel /mnt/casper/vmlinuz \
    -initrd /mnt/casper/initrd \
    -append 'autoinstall ds=nocloud-net;s=http://_gateway:3003/'

This will boot, download the config from the server set up in the previous step and run the install. The installer reboots at the end but the -no-reboot flag to kvm means that kvm will exit when this happens. It should take about 5 minutes.

Boot the installed system

kvm -no-reboot -m 1024 \
    -drive file=image.img,format=raw,cache=none,if=virtio

This will boot into the freshly installed system and you should be able to log in as ubuntu/ubuntu.

Using another volume to provide the autoinstall config

This is the method to use when you want to create media that you can just plug into a system to have it be installed.

Download the ISO

cd ~/Downloads
wget http://releases.ubuntu.com/20.04/ubuntu-20.04-live-server-amd64.iso

Create your user-data & meta-data files

mkdir -p ~/cidata
cd ~/cidata
cat > user-data << 'EOF'
#cloud-config
autoinstall:
  version: 1
  identity:
    hostname: ubuntu-server
    password: "$6$exDY1mhS4KUYCE/2$zmn9ToZwTKLhCw.b4/b.ZRTIZM30JZ4QrOQ2aOXJ8yk96xpcCof0kxKwuX1kqLG/ygbJ1f8wxED22bTL4F46P0"
    username: ubuntu
EOF
touch meta-data

The crypted password is just “ubuntu”.

Create an ISO to use as a cloud-init data source

sudo apt install cloud-image-utils
cloud-localds ~/seed.iso user-data meta-data

Create a target disk

truncate -s 10G image.img

Run the install!

kvm -no-reboot -m 1024 \
    -drive file=image.img,format=raw,cache=none,if=virtio \
    -drive file=~/seed.iso,format=raw,cache=none,if=virtio \
    -cdrom ~/Downloads/ubuntu-20.04-live-server-amd64.iso

This will boot and run the install. Unless you interrupt boot to add ‘autoinstall’ to the kernel command line, the installer will prompt for confirmation before touching the disk.

The installer reboots at the end but the -no-reboot flag to kvm means that kvm will exit when this happens.

The whole process should take about 5 minutes.

Boot the installed system

kvm -no-reboot -m 1024 \
    -drive file=image.img,format=raw,cache=none,if=virtio

This will boot into the freshly installed system and you should be able to log in as ubuntu/ubuntu.

Last updated 2 months ago. Help improve this document in the forum.