So, I've set up a Proxmox cluster using Intel NUC Skull i7 32GB RAM machines with 1TB M.2 SSDs and loving it! I noticed the Proxmox LXD images didn't include the latest Ubuntu 23.04 Server I wanted to use for some light-ish docker deployments. After some research, I worked out that you can download templates from images.linuxcontainers.org, but it wasn't clear on what you needed to download!
Go to https://us.lxd.images.canonical.com/images/
Click on ubuntu, then lunar and finally amd64
Select what image you want and then the latest folder date:-
a) Cloud is the minimal image
b) Default is the server image
c) Desktop is the desktop image (doh!)
The download URL you need for Proxmox CT Template images is the file:-
rootfs.tar.xz
Right-hand click on the link, copy the download URL and use this within Proxmox to download the image.
You can down use this template to start a container on Proxmox
LXD Applications can be downloaded from the following link:-
http://mirror.turnkeylinux.org/turnkeylinux/images/proxmox/
Look for the images to download with the following suffix:-
*.amd64.tar.gz