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23th chunk of `content/reference/compose-file/services.md`
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The short syntax uses a single string with colon-separated values to specify a volume mount
(`VOLUME:CONTAINER_PATH`), or an access mode (`VOLUME:CONTAINER_PATH:ACCESS_MODE`).

- `VOLUME`: Can be either a host path on the platform hosting containers (bind mount) or a volume name.
- `CONTAINER_PATH`: The path in the container where the volume is mounted.
- `ACCESS_MODE`: A comma-separated `,` list of options:
  - `rw`: Read and write access. This is the default if none is specified.
  - `ro`: Read-only access.
  - `z`: SELinux option indicating that the bind mount host content is shared among multiple containers.
  - `Z`: SELinux option indicating that the bind mount host content is private and unshared for other containers.

> [!NOTE]
>
> The SELinux re-labeling bind mount option is ignored on platforms without SELinux.

> [!NOTE]
> Relative host paths are only supported by Compose that deploy to a
> local container runtime. This is because the relative path is resolved from the Compose file’s parent
> directory which is only applicable in the local case. When Compose deploys to a non-local
> platform it rejects Compose files which use relative host paths with an error. To avoid ambiguities
> with named volumes, relative paths should always begin with `.` or `..`.

> [!NOTE]
>
> For bind mounts, the short syntax creates a directory at the source path on the host if it doesn't exist. This is for backward compatibility with `docker-compose` legacy. 
> It can be prevented by using long syntax and setting `create_host_path` to `false`.

#### Long syntax

The long form syntax lets you configure additional fields that can't be
expressed in the short form.

- `type`: The mount type. Either `volume`, `bind`, `tmpfs`, `image`, `npipe`, or `cluster`
- `source`: The source of the mount, a path on the host for a bind mount, a Docker image reference for an image mount, or the
  name of a volume defined in the
  [top-level `volumes` key](volumes.md). Not applicable for a tmpfs mount.
- `target`: The path in the container where the volume is mounted.
- `read_only`: Flag to set the volume as read-only.
- `bind`: Used to configure additional bind options:
  - `propagation`: The propagation mode used for the bind.
Title: Compose File Reference: Volumes - Short and Long Syntax
Summary
This section describes the short and long syntax for defining volumes in a Compose file. The short syntax uses colon-separated values for volume mounting and access modes. It defines the meaning of VOLUME, CONTAINER_PATH, and ACCESS_MODE, including options like 'rw', 'ro', 'z', and 'Z' for SELinux contexts. The section also explains the long syntax for configuring additional fields like type, source, target, read_only, and bind propagation modes.