Bind mounts don't have a name and they can't be named. Top-level volumes key always declares volumes, never bind mounts. This volume needs to be declared in the same file in the top-level volumes key declaration. If a source is present and it's not a path, then Docker Compose assumes you're referring to a named volume. The directory's path on the host system is by default /var/lib/docker/volumes//_data, where is a random ID assigned to the volume as its name. When only a target is specified, without a source, Docker Compose will create an anonymous directory and mount it as a volume to the target path inside the container. Docker Compose is smart about recognising which variety is used and whether to use a volume or bind mount. This optionality leads to three unique variations you can use to configure a container's volumes. MODE is a mount option which can be read-only or read-write. TARGET is an absolute path in the container. SOURCE can be a named volume or a (relative or absolute) path on the host system. The volume configuration has a short syntax format that is defined as: This configuration has a short (and a long) syntax format. That's where you configure volumes for a specific service/container such as a database or web server. In this article, we'll talk about the nested volumes key. Declares volumes which can be referenced from multiple services. Configures volumes for a particular service. In docker-compose.yml, the volumes key can appear in two different places. рџ”—Two volumes keys in docker-compose.ymlД«efore we talk about the different ways to specify volumes, let's first clarify which volumes key we're referring to. I list and explain them in this article below. The different variations are essentially three unique forms. You'll simply know by looking at the syntax whether a volume or a bind mount is used behind the scenes. I wrote this article so that next time you read a Docker Compose file, you won't have to guess anymore. Whenever I had to read a docker-compose.yml file, I had to look up the official documentation or run a quick local experiment to figure out how Docker Compose would mount the directories into the container.

Which of these are volumes and which are a bind mounts?

Docker Compose allows you to configure volumes and bind mounts using a short syntax.

Docker run image mount volume