This is a kind of special restart policy and probably the most often used. By using the on-failure restart policy, you instruct Docker to restart your container whenever it exits with a non-zero exit status and not restart otherwise. That's the reason we have begun explaining restart policies with the exit codes. You can optionally provide a number of times for Docker to attempt to restart the container. The syntax of this restart policy is also a little bit different, because using this policy, you can also specify a maximum number of tries that Docker will make to automatically restart the container.
Consider this example:
$ docker run --restart=on-failure:5 rest-example
The preceding command will run the container with our ...
