Could not configure HTTPS connector for Docker repository

Symptom

On startup, you may see a line like this in your nexus.log

2015-11-13 13:55:55,592-0400 WARN  [FelixStartLevel] *SYSTEM org.sonatype.nexus.repository.docker.internal.DockerConnectorFacetImpl - Could not configure HTTPS connector on port 18443 for docker repository docker-all
org.sonatype.nexus.bootstrap.jetty.UnsupportedHttpSchemeException: Unsupported HTTP Scheme: https

Cause

Docker registries are required to use HTTPS. This message means that you have not configured Jetty with a keystore from which it can load a TLS certificate for the Docker HTTPS connectors.

Solution

Configure Jetty with an SSL certificate to use when servicing Docker registry requests. See the instructions in our documentation for configuring Jetty HTTPS connections.