Home • Explore • Blog • CI
☰



docker
2nd chunk of `content/manuals/engine/storage/tmpfs.md`
6c34834dfdefec10341b0f4eb6d825894139cee0fd20fe120000000100000be1
The first field is the container path to mount into a tmpfs. The second field
is optional and lets you set mount options. Valid mount options for `--tmpfs`
include:

| Option       | Description                                                                                 |
| ------------ | ------------------------------------------------------------------------------------------- |
| `ro`         | Creates a read-only tmpfs mount.                                                            |
| `rw`         | Creates a read-write tmpfs mount (default behavior).                                        |
| `nosuid`     | Prevents `setuid` and `setgid` bits from being honored during execution.                    |
| `suid`       | Allows `setuid` and `setgid` bits to be honored during execution (default behavior).        |
| `nodev`      | Device files can be created but are not functional (access results in an error).            |
| `dev`        | Device files can be created and are fully functional.                                       |
| `exec`       | Allows the execution of executable binaries in the mounted file system.                     |
| `noexec`     | Does not allow the execution of executable binaries in the mounted file system.             |
| `sync`       | All I/O to the file system is done synchronously.                                           |
| `async`      | All I/O to the file system is done asynchronously (default behavior).                       |
| `dirsync`    | Directory updates within the file system are done synchronously.                            |
| `atime`      | Updates file access time each time the file is accessed.                                    |
| `noatime`    | Does not update file access times when the file is accessed.                                |
| `diratime`   | Updates directory access times each time the directory is accessed.                         |
| `nodiratime` | Does not update directory access times when the directory is accessed.                      |
| `size`       | Specifies the size of the tmpfs mount, for example, `size=64m`.                             |
| `mode`       | Specifies the file mode (permissions) for the tmpfs mount (for example, `mode=1777`).       |
| `uid`        | Specifies the user ID for the owner of the tmpfs mount (for example, `uid=1000`).           |
| `gid`        | Specifies the group ID for the owner of the tmpfs mount (for example, `gid=1000`).          |
| `nr_inodes`  | Specifies the maximum number of inodes for the tmpfs mount (for example, `nr_inodes=400k`). |
| `nr_blocks`  | Specifies the maximum number of blocks for the tmpfs mount (for example, `nr_blocks=1024`). |

```console {title="Example"}
$ docker run --tmpfs /data:noexec,size=1024,mode=1777
```

Not all tmpfs mount features available in the Linux mount command are supported
with the `--tmpfs` flag. If you require advanced tmpfs options or features, you
may need to use a privileged container or configure the mount outside of
Title: Options for --tmpfs in Docker
Summary
This section details the options available when using the `--tmpfs` flag in Docker to mount a tmpfs volume. It explains that the flag takes a container path and optional mount options, then provides a table listing available options such as `ro`, `rw`, `nosuid`, `size`, `mode`, `uid`, and `gid`, along with their descriptions and an example of usage.