docker-logout (1) - Linux Man Pages
docker-logout: Log out from a Docker registry
docker-logout - Log out from a Docker registry
docker logout [SERVER]
Log out of a Docker Registry located on the specified SERVER. You can specify a URL or a hostname for the SERVER value. If you do not specify a SERVER, the command attempts to log you out of Docker's public registry located at https://registry-1.docker.io/ by default.
Log out from a registry on your localhost
# docker logout localhost:8080