1229e735ac
this adds support for structural includes to nixos-render-docs. structural includes provide a way to denote the (sub)structure of the nixos manual in the markdown source files, very similar to how we used literal docbook blocks before, and are processed by nixos-render-docs without involvement of xml tooling. this will ultimately allow us to emit the nixos manual in other formats as well, e.g. html, without going through docbook at all. alternatives to this source layout were also considered: a parallel structure using e.g. toml files that describe the document tree and links to each part is possible, but much more complicated to implement than the solution chosen here and makes it harder to follow which files have what substructure. it also makes it much harder to include a substructure in the middle of a file. much the same goes for command-line arguments to the converter, only that command-lined arguments are even harder to specify correctly and cannot be reasonably pulled together from many places without involving another layer of tooling. cli arguments would also mean that the manual structure would be fixed in default.nix, which is also not ideal.
42 lines
1.7 KiB
Markdown
42 lines
1.7 KiB
Markdown
# File Systems {#ch-file-systems}
|
|
|
|
You can define file systems using the `fileSystems` configuration
|
|
option. For instance, the following definition causes NixOS to mount the
|
|
Ext4 file system on device `/dev/disk/by-label/data` onto the mount
|
|
point `/data`:
|
|
|
|
```nix
|
|
fileSystems."/data" =
|
|
{ device = "/dev/disk/by-label/data";
|
|
fsType = "ext4";
|
|
};
|
|
```
|
|
|
|
This will create an entry in `/etc/fstab`, which will generate a
|
|
corresponding [systemd.mount](https://www.freedesktop.org/software/systemd/man/systemd.mount.html)
|
|
unit via [systemd-fstab-generator](https://www.freedesktop.org/software/systemd/man/systemd-fstab-generator.html).
|
|
The filesystem will be mounted automatically unless `"noauto"` is
|
|
present in [options](#opt-fileSystems._name_.options). `"noauto"`
|
|
filesystems can be mounted explicitly using `systemctl` e.g.
|
|
`systemctl start data.mount`. Mount points are created automatically if they don't
|
|
already exist. For `device`, it's best to use the topology-independent
|
|
device aliases in `/dev/disk/by-label` and `/dev/disk/by-uuid`, as these
|
|
don't change if the topology changes (e.g. if a disk is moved to another
|
|
IDE controller).
|
|
|
|
You can usually omit the file system type (`fsType`), since `mount` can
|
|
usually detect the type and load the necessary kernel module
|
|
automatically. However, if the file system is needed at early boot (in
|
|
the initial ramdisk) and is not `ext2`, `ext3` or `ext4`, then it's best
|
|
to specify `fsType` to ensure that the kernel module is available.
|
|
|
|
::: {.note}
|
|
System startup will fail if any of the filesystems fails to mount,
|
|
dropping you to the emergency shell. You can make a mount asynchronous
|
|
and non-critical by adding `options = [ "nofail" ];`.
|
|
:::
|
|
|
|
```{=include=} sections
|
|
luks-file-systems.section.md
|
|
sshfs-file-systems.section.md
|
|
```
|