short-name-mode="enforcing", unqualified-search-registries

[westurner]

If the repo2docker Dockerfile template is changed, changing /etc/containers/registries.conf shouldn't be necessary for repo2docker/repo2podman, at least:

FROM buildpack-deps:bionic             # short-name
FROM docker.io/buildpack-deps:bionic   # "qulified" name

[westurner]

From https://marcusnoble.co.uk/2021-09-01-migrating-from-docker-to-podman/ :

If we want Podman to perform more like Docker we'll want to change this value to permissive:

sudo sed -i 's/short-name-mode="enforcing"/short-name-mode="permissive"/g' /etc/containers/registries.conf

There's one more property in this file that it's worth at least being aware of.

unqualified-search-registries = ["registry.fedoraproject.org", "registry.access.redhat.com", "docker.io", "quay.io"]

This property contains a list of all the registries that will be checked (in order) when looking up a short name image. Be sure the values in here are ones that you trust!

[manics]

Done in jupyterhub/repo2docker#909