Creating a Btrfs Layout
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   Btrfs is a type of file system, but it has several features
   characteristic of a storage device. It is designed to make the
   file system tolerant of errors, and to facilitate the detection
   and repair of errors when they occur. It uses checksums to
   ensure the validity of data and metadata, and maintains
   snapshots of the file system that can be used for backup or
   repair.

   Creating a Btrfs layout is somewhat similar to LVM (described
   in Creating a Logical Volume Managament (LVM) Layout) with
   slightly different terminology. A Btrfs volume is the
   equivalent of an LVM volume group, and a Btrfs subvolume is
   similar to a LVM logical volume. An important difference to
   note is how Anaconda reports sizes for separate mount points:
   For LVM, the exact size of each logical volume is shown next to
   each mount point in the left pane, while with Btrfs, the total
   size of the entire volume is shown next to each subvolume.

Warning

   Some partition types - notably the /boot and /usr directories
   and the BIOS Boot and EFI partitions - can not be placed on
   Btrfs subvolumes. Use standard physical volumes for them (or an
   LVM logical volume for /usr). See Recommended Partitioning
   Scheme for more information.

   Follow the procedure below to create Btrfs volumes and
   subvolumes:

   Procedure 1. Creating Btrfs Subvolumes and Volumes
    1. Click the + button at the bottom of the list showing
       existing mount points. A new dialog window will open.
    2. In the new dialog window, specify a mount point for which
       you want to create a separate logical volume - for example,
       /. Optionally, specify a size for the volume using standard
       units such as MB or GB (for example, 50GB). Then, click Add
       mount point to add the volume and return to the main
       partitioning screen.

Note
       When creating a mount point for swap on Btrfs, specify the
       mount point as swap.
    3. The mount point has now been created using the default
       settings, which means it has been created as an LVM logical
       volume. Select the newly created mount point in the left
       pane to configure it further, and convert it to a Btrfs
       subvolume by changing the Device Type option to Btrfs.
       Then, click Update Settings in the bottom right corner of
       the screen.
    4. In the Volume menu, you can see that the subvolume has been
       assigned to an automatically created volume, which is named
       after the Fedora variant you are installing (for example,
       fedora-server00. Click the Modify button under the
       drop-down menu to access the volume settings.
    5. In the Configure Volume dialog, you can change the volume's
       name, its RAID level (see Device, File System and RAID
       Types for information about available RAID types), and you
       can also specify which physical devices (disks) this volume
       should reside on. You can select one or more disks which
       will be used to hold this volume by holding down Ctrl and
       clicking each disk in the list.

Note
       If you select a redundant RAID type (such as RAID1
       (Redundancy)), the volume will take up twice its actual
       size on your disks. A 5 GB volume with RAID1 will take up
       10 GB of space.
       You can also make sure that the volume is encrypted by
       selecting the Encrypt option; this will enable LUKS
       encryption for the entire volume. See the Fedora Security
       Guide, available at http://docs.fedoraproject.org/, for
       information about LUKS disk encryption.
       Additionally, you can set a fixed size for the volume by
       selecting the Fixed option from the Size policy menu and
       entering a size for the volume group.
       After you finish configuring the Btrfs volume settings,
       click Save to return to the main Manual Partitioning
       screen.
    6. If you need to create more than one Btrfs volume, open the
       Volume drop-down menu and select the Create a new volume
       group option. A new dialog window will open, identical to
       the one described in the previous step. Again, select a
       name, storage devices, encryption settings, RAID level and
       size policy for the new volume, and click Save. The new
       volume will then become available in the Volume Group
       drop-down menu; you can then go through your existing mount
       points and change this setting to assign them to a
       different volume.
    7. Configure other settings specific to the subvolume - its
       Mount Point, Desired Capacity, File System, and Name. Press
       Update Settings to apply any changes to the configuration.

   Repeat this procedure for any additional Btrfs subvolumes you
   want to create. Note that when creating additional subvolumes,
   a new volume is not automatically created each time; instead,
   any additional subvolumes are assigned to an existing volume.

   For each mount point you create, review its settings and make
   sure that it is assigned to the correct volume, that it has
   sufficient capacity, and that it has a descriptive name so you
   can identify the subvolume later if you need to.
