LXC/LXD

Profiles

cloud-init

The following content is based off LXC's documentation and various searches. You may want to first have a look at the official documentation.

Here's a short example of a profile with a cloud-init configuration.

config:
  user.user-data: |
    #cloud-config
    ssh_authorized_keys:
      - {{ Insert your SSH public key }}
    package_update: true
    packages:
      - htop
      - vim
      - tmux
      - mtr-tiny
    runcmd: # Runs on first boot, but later than bootcmd
      - mkdir -pv /etc/vim
      - curl -o /etc/vim/vimrc.local https://raw.githubusercontent.com/amix/vimrc/master/vimrcs/basic.vim
    bootcmd: # Runs on first boot, but earlier than runcmd
      - date

There are a few ways to edit a profile, here's the one that worked best for me.

1. Create a new profile based on the default one: lxc profile copy default {{ profile name }}

2. Pipe base profile to a new file in the home directory: lxc profile show {{ profile name }} > ~/{{ profile name }}.yaml

3. Edit the new profile file with your favorite editor

4. Pipe the modified profile back to LXC: cat ~/{{ profile name }} | lxc profile edit {{ profile name }}

5. Start a new instance with the profile: lxc launch ubuntu:20.04 local:ubuntu_cloud-init -p {{ profile name }}

6. Check the status of cloud-init inside the instance: lxc exec ubuntu_cloud-init cloud-init status

It can take a few minutes for cloud-init to run all the instructions.

Here's the whole file for reference purposes. Yours will most likely defer depending on the configuration done with lxd ini.

config:
  user.user-data: |
    #cloud-config
    ssh_authorized_keys:
      - {{ Insert your SSH public key }}
    package_update: true
    packages:
      - htop
      - vim
      - tmux
      - mtr-tiny
    runcmd: # Runs on first boot, but later than bootcmd
      - mkdir -pv /etc/vim
      - curl -o /etc/vim/vimrc.local https://raw.githubusercontent.com/amix/vimrc/master/vimrcs/basic.vim
    bootcmd: # Runs on first boot, but really early
      - date
description: Initial setup
devices:
  eth0:
    name: eth0
    network: lxdbr0
    type: nic
  root:
    path: /
    pool: default
    type: disk
name: admin
used_by: []

References

• LXD documentation

• cloud-init documentation