You need to have Docker running on your local machine, and the user you're running abra from must have permission to control Docker. If you're having trouble, try adding yourself to the `docker` group, and re-logging.
The `-p` or `--provision` flag means that `abra` will install Docker and initialise the [new single-host swarm](https://docs.docker.com/engine/swarm/key-concepts/) on your server. If you've already followed the steps in [the server setup](/operators/tutorial/#server-setup) step, then `abra` should not need to do any work.
The `-a` or `--ask-sudo-pass` flag means that abra will use `ssh-askpass` on your server to ask for sudo pass. Skip if you have passwordless sudo on your server or if logging in as root.