How to allow multiple '--insecure-registry' for docker registry

Docker 17.xx +

1. Edit the daemon.json file, whose default location is /etc/docker/daemon.json on Linux or C:\ProgramData\docker\config\daemon.json on Windows Server

   If the daemon.json file does not exist, create it.

   {
         "insecure-registries": ["myregistry:5000", "anotherregistry:5000"]
   }
   

2. Restart Docker for the changes to take effect. In Ubuntu would be like this:

   $ sudo systemctl daemon-reload
   $ sudo systemctl restart docker
   

Find more details in official documentation page https://docs.docker.com/registry/insecure/

You can specify multiple insecure registries by lining them up:

--insecure-registry IP1:PORT --insecure-registry IP2:PORT --insecure-registry IP3:PORT

Source: https://github.com/docker/docker/issues/9026