Btrfs: Difference between revisions

Line 3:

{{note| Use [https://github.com/nix-community/disko/ disko] to manage your NixOS storage layout declaratively. The following shows a manual approach as seen in traditional Linux distributions.}}

= Installation =

= Installation of NixOS on btrfs =

{{note|The following example is for EFI enabled systems. Adjust commands accordingly for a BIOS installation.}}

Line 164:

== Subvolumes ==

~~Create~~ a subvolume

To display all subvolumes within a mounted btrfs filesystem:

btrfs subvolume list -t /mnt

</syntaxhighlight>

To create a new subvolume at a specified location:

Line 170:

Line 176:

</syntaxhighlight>

~~Remove a~~ subvolume

To remove an existing subvolume:

btrfs subvolume delete /mnt/nixos

</syntaxhighlight>

=== Top level vs nested subvolumes ===

In btrfs, subvolumes can be created either at the top level of the filesystem or within other subvolumes

* Top level subvolumes are created directly under the filesystem's root. By default, the root volume id is 5. Top level subvolumes are easier to snapshotted, rolled back or destroyed independently. This is good for things such as <code>/home</code> or <code>/nix</code>.

* Nested subvolumes are created inside an existing subvolume or directory within the filesystem. All nested subvolumes inherit the mount status of their parent unless mounted seperately. This layout is useful for organizing related subvolumes under a common namespace. For example, a top-level subvolume such as <code>/srv/nfs</code> can contain multiple nested subvolumes like <code>/srv/nfs/export1</code> and <code>/srv/nfs/export2</code>.

== Snapshots ==

@@ Line 3: / Line 3: @@
 {{note| Use [https://github.com/nix-community/disko/ disko] to manage your NixOS storage layout declaratively. The following shows a manual approach as seen in traditional Linux distributions.}}
-= Installation =
+= Installation of NixOS on btrfs =
 {{note|The following example is for EFI enabled systems. Adjust commands accordingly for a BIOS installation.}}
@@ Line 164: / Line 164: @@
 == Subvolumes ==
-Create a subvolume
+To display all subvolumes within a mounted btrfs filesystem:
+<syntaxhighlight lang="bash">
+btrfs subvolume list -t /mnt
+</syntaxhighlight>
+To create a new subvolume at a specified location:
 <syntaxhighlight lang="bash">
@@ Line 170: / Line 176: @@
 </syntaxhighlight>
-Remove a subvolume
+To remove an existing subvolume:
 <syntaxhighlight lang="bash">
 btrfs subvolume delete /mnt/nixos
 </syntaxhighlight>
+=== Top level vs nested subvolumes ===
+In btrfs, subvolumes can be created either at the top level of the filesystem or within other subvolumes
+* Top level subvolumes are created directly under the filesystem's root. By default, the root volume id is 5. Top level subvolumes are easier to snapshotted, rolled back or destroyed independently. This is good for things such as <code>/home</code> or <code>/nix</code>.
+* Nested subvolumes are created inside an existing subvolume or directory within the filesystem. All nested subvolumes inherit the mount status of their parent unless mounted seperately. This layout is useful for organizing related subvolumes under a common namespace. For example, a top-level subvolume such as <code>/srv/nfs</code> can contain multiple nested subvolumes like <code>/srv/nfs/export1</code> and <code>/srv/nfs/export2</code>.
 == Snapshots ==