I want to configure a replication between harbor and a docker registry.
The docker registry is secured by self-signed certificates, which I copied to /etc/docker/certs.d/dockerregistry.mydomain/ (.cert , .crt files) on the harbor host.

But when I configure the registry in harbor with verify remote cert, the failure "failed to ping endpoint" occurs.

What is missing or what am I doing wrong? 

(I am using v2.0.1 and of course did a docker-compose down and up already)