Thanks. It seems that using distrobuilder would be more complicated than I had hoped: there’s lots to understand in the yaml files. But I stumbled on this alternative approach:
- Create an empty container using the REST API (LXD: How to create an empty container (rootfs empty) - #3 by stgraber)
- Mount the storage (e.g. sudo zfs mount poolname/containername)
- Untar into the rootfs folder
- Fix the permissions: chgrp -R 100000:100000 rootfs
- Unmount the storage
- Start the container
This works for me (so far!)