[[_docker_variable_override]]

=== Docker Registry Environment Variable Override Installation

Often times it is appropriate to use a simple environment variable override for develop or POC Docker registries.  While this apporach is usually not recommended for production use, it can be helpful when one requires quick-and-dirty way to stand up a registry.  Simply use the _Variable Override_ Format Option from the client installation tab, and an output should appear like the one below:

    REGISTRY_AUTH_TOKEN_REALM: http://localhost:8080/auth/auth/realms/master/protocol/docker-v2/auth
    REGISTRY_AUTH_TOKEN_SERVICE: docker-test
    REGISTRY_AUTH_TOKEN_ISSUER: http://localhost:8080/auth/auth/realms/master

WARNING: Don't forget to configure the `REGISTRY_AUTH_TOKEN_ROOTCERTBUNDLE` override with the location of the {{book.project.name}} realm's pulic certificate.  The auth configuration will not work without this argument.