Managing Docker Containers: Listing, Stopping, Starting, and Naming

You should see output like the following. ```console Hello, Docker! ``` ## List containers Since you ran your container in the background, how do you know if your container is running or what other containers are running on your machine? Well, to see a list of containers running on your machine, run `docker ps`. This is similar to how you use the ps command in Linux to see a list of processes. You should see output like the following. ```console CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 3074745e412c docker-rust-image "/bin/server" 8 seconds ago Up 7 seconds 0.0.0.0:3001->8000/tcp wonderful_kalam ``` The `docker ps` command provides a bunch of information about your running containers. You can see the container ID, the image running inside the container, the command that was used to start the container, when it was created, the status, ports that were exposed, and the name of the container. You are probably wondering where the name of your container is coming from. Since you didn’t provide a name for the container when you started it, Docker generated a random name. You’ll fix this in a minute, but first you need to stop the container. To stop the container, run the `docker stop` command which does just that, stops the container. You need to pass the name of the container or you can use the container ID. ```console $ docker stop wonderful_kalam wonderful_kalam ``` Now, rerun the `docker ps` command to see a list of running containers. ```console $ docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES ``` ## Stop, start, and name containers You can start, stop, and restart Docker containers. When you stop a container, it's not removed, but the status is changed to stopped and the process inside the container is stopped. When you ran the `docker ps` command in the previous module, the default output only shows running containers. When you pass the `--all` or `-a` for short, you see all containers on your machine, irrespective of their start or stop status. ```console $ docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 3074745e412c docker-rust-image "/bin/server" 3 minutes ago Exited (0) 6 seconds ago wonderful_kalam 6cfa26e2e3c9 docker-rust-image "/bin/server" 14 minutes ago Exited (0) 5 minutes ago friendly_montalcini 4cbe94b2ea0e docker-rust-image "/bin/server" 15 minutes ago Exited (0) 14 minutes ago tender_bose ``` You should now see several containers listed. These are containers that you started and stopped but you haven't removed. Restart the container that you just stopped. Locate the name of the container you just stopped and replace the name of the container in following restart command. ```console $ docker restart wonderful_kalam ``` Now list all the containers again using the `docker ps` command. ```console $ docker ps --all

This section explains how to list all containers (both running and stopped) using `docker ps -a`, how to stop a container using `docker stop`, and how to restart a stopped container using `docker restart`. It also highlights how Docker automatically assigns a random name to a container if one isn't provided during creation.