Thanks @rseddon. The sample config I had found on your help did not mention port-forwarding :
https://help.sonatype.com/repomanager2/installing-and-running/running-behind-a-reverse-proxy
(I’m aware that the URL mentions NXRM2, but I assume that the nginx config should not change regardless of the back-end).
I keep note of your comment about the registry’s endpoint as well.