systemd-gpt-auto-generator(8)
NAME
systemd-gpt-auto-generator - Generator for automatically discovering
and mounting root, /home and /srv partitions, as well as discovering
and enabling swap partitions, based on GPT partition type GUIDs.
SYNOPSIS
/lib/systemd/system-generators/systemd-gpt-auto-generator
DESCRIPTION
systemd-gpt-auto-generator is a unit generator that automatically
discovers root, /home, /srv and swap partitions and creates mount and
swap units for them, based on the partition type GUIDs of GUID
partition tables (GPT). It implements the Discoverable Partitions
Specification[1]. Note that this generator has no effect on non-GPT
systems, or where the directories under the mount points are already
non-empty. Also, on systems where the units are explicitly configured
(for example, listed in fstab(5)), the units this generator creates are
overridden, but additional automatic dependencies might be created.
This generator will only look for root partitions on the same physical
disk the EFI System Partition (ESP) is located on. It will only look
for the other partitions on the same physical disk the root file system
is located on. These partitions will not be searched on systems where
the root file system is distributed on multiple disks, for example via
btrfs RAID.
systemd-gpt-auto-generator is useful for centralizing file system
configuration in the partition table and making manual configuration in
/etc/fstab or suchlike unnecessary.
This generator looks for the partitions based on their partition type
GUID. The following partition type GUIDs are identified:
Table 1. Partition Type GUIDs
Partition Type GUID Name Explanation
44479540-f297-41b2-9af7-d131d5f0458a Root Partition On 32-bit x86
(x86) systems, the first
x86 root partition
on the disk the EFI
ESP is located on
is mounted to the
root directory /.
4f68bce3-e8cd-4db1-96e7-fbcaf984b709 Root Partition On 64-bit x86
(x86-64) systems, the first
x86-64 root
partition on the
disk the EFI ESP is
located on is
mounted to the root
directory /.
69dad710-2ce4-4e3c-b16c-21a1d49abed3 Root Partition On 32-bit ARM
(32-bit ARM) systems, the first
ARM root partition
on the disk the EFI
ESP is located on
is mounted to the
root directory /.
b921b045-1df0-41c3-af44-4c6f280d3fae Root Partition On 64-bit ARM
(64-bit ARM) systems, the first
ARM root partition
on the disk the EFI
ESP is located on
is mounted to the
root directory /.
933ac7e1-2eb4-4f13-b844-0e14e2aef915 Home Partition The first home
partition on the
disk the root
partition is
located on is
mounted to /home.
3b8f8425-20e0-4f3b-907f-1a25a76f98e8 Server Data The first server
Partition data partition on
the disk the root
partition is
located on is
mounted to /srv.
0657fd6d-a4ab-43c4-84e5-0933c84b4f4f Swap All swap partitions
located on the disk
the root partition
is located on are
enabled.
c12a7328-f81f-11d2-ba4b-00a0c93ec93b EFI System The first ESP
Partition (ESP) located on the disk
the root partition
is located on is
mounted to /boot or
/efi, see below.
The /home and /srv partitions may be encrypted in LUKS format. In this
case, a device mapper device is set up under the names /dev/mapper/home
and /dev/mapper/srv. Note that this might create conflicts if the same
partition is listed in /etc/crypttab with a different device mapper
device name.
Mount and automount units for the EFI System Partition (ESP) are
generated on EFI systems. The ESP is mounted to /boot, unless a mount
point directory /efi exists, in which case it is mounted there. Since
this generator creates an automount unit, the mount will only be
activated on-demand, when accessed. On systems where /boot (or /efi if
it exists) is an explicitly configured mount (for example, listed in
fstab(5)) or where the /boot (or /efi) mount point is non-empty, no
mount units are generated.
When using this generator in conjunction with btrfs file systems, make
sure to set the correct default subvolumes on them, using btrfs
subvolume set-default.
systemd-gpt-auto-generator implements systemd.generator(7).
SEE ALSO
systemd(1), systemd.mount(5), systemd.swap(5), systemd-fstab-
generator(8), systemd-cryptsetup@.service(8), cryptsetup(8), fstab(5),
btrfs(8)
NOTES
1. Discoverable Partitions Specification
http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/
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