[Podman] rootless-cni-infra - when & how?

Hi guys. I  assume that 'rootless-cni-infra' gets created somewhere under the hood without user intervention and I wonder how and when, as I see this: .. ERRO[0000] error starting some container dependencies ERRO[0000] "rootless CNI infra image not present - please build image from https://github.com/containers/podman/blob/v3.0.1-rhel/contrib/rootless-cn... and tag as \"rootless-cni-infra\"" Error: error starting some containers: internal libpod error Would somebody care to shed some light on it? many thanks, L.