1SYSTEMD-GPT-AUTO-GENERATOR(s8y)stemd-gpt-auto-generatSoYrSTEMD-GPT-AUTO-GENERATOR(8)
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NAME

6       systemd-gpt-auto-generator - Generator for automatically discovering
7       and mounting root, /home and /srv partitions, as well as discovering
8       and enabling swap partitions, based on GPT partition type GUIDs.
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SYNOPSIS

11       /usr/lib/systemd/system-generators/systemd-gpt-auto-generator
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DESCRIPTION

14       systemd-gpt-auto-generator is a unit generator that automatically
15       discovers root, /home, /srv and swap partitions and creates mount and
16       swap units for them, based on the partition type GUIDs of GUID
17       partition tables (GPT), see UEFI Specification[1], chapter 5. It
18       implements the Discoverable Partitions Specification[2]. Note that this
19       generator has no effect on non-GPT systems, or where the directories
20       under the mount points are already non-empty. Also, on systems where
21       the units are explicitly configured (for example, listed in fstab(5)),
22       the units this generator creates are overridden, but additional
23       implicit dependencies might be created.
24
25       This generator will only look for root partitions on the same physical
26       disk the EFI System Partition (ESP) is located on. It will only look
27       for the other partitions on the same physical disk the root file system
28       is located on. These partitions will not be searched for on systems
29       where the root file system is distributed on multiple disks, for
30       example via btrfs RAID.
31
32       systemd-gpt-auto-generator is useful for centralizing file system
33       configuration in the partition table and making configuration in
34       /etc/fstab unnecessary.
35
36       This generator looks for the partitions based on their partition type
37       GUID. The following partition type GUIDs are identified:
38
39       Table 1. Partition Type GUIDs
40       ┌─────────────────────────────────────┬─────────────────┬─────────────────────┐
41Partition Type GUID                  Name            Explanation         
42       ├─────────────────────────────────────┼─────────────────┼─────────────────────┤
43       │44479540-f297-41b2-9af7-d131d5f0458a │ Root Partition  │ On 32-bit x86       │
44       │                                     │ (x86)           │ systems, the first  │
45       │                                     │                 │ x86 root partition  │
46       │                                     │                 │ on the disk the EFI │
47       │                                     │                 │ ESP is located on   │
48       │                                     │                 │ is mounted to the   │
49       │                                     │                 │ root directory /.   │
50       ├─────────────────────────────────────┼─────────────────┼─────────────────────┤
51       │4f68bce3-e8cd-4db1-96e7-fbcaf984b709 │ Root Partition  │ On 64-bit x86       │
52       │                                     │ (x86-64)        │ systems, the first  │
53       │                                     │                 │ x86-64 root         │
54       │                                     │                 │ partition on the    │
55       │                                     │                 │ disk the EFI ESP is │
56       │                                     │                 │ located on is       │
57       │                                     │                 │ mounted to the root │
58       │                                     │                 │ directory /.        │
59       ├─────────────────────────────────────┼─────────────────┼─────────────────────┤
60       │69dad710-2ce4-4e3c-b16c-21a1d49abed3 │ Root Partition  │ On 32-bit ARM       │
61       │                                     │ (32-bit ARM)    │ systems, the first  │
62       │                                     │                 │ ARM root partition  │
63       │                                     │                 │ on the disk the EFI │
64       │                                     │                 │ ESP is located on   │
65       │                                     │                 │ is mounted to the   │
66       │                                     │                 │ root directory /.   │
67       ├─────────────────────────────────────┼─────────────────┼─────────────────────┤
68       │b921b045-1df0-41c3-af44-4c6f280d3fae │ Root Partition  │ On 64-bit ARM       │
69       │                                     │ (64-bit ARM)    │ systems, the first  │
70       │                                     │                 │ ARM root partition  │
71       │                                     │                 │ on the disk the EFI │
72       │                                     │                 │ ESP is located on   │
73       │                                     │                 │ is mounted to the   │
74       │                                     │                 │ root directory /.   │
75       ├─────────────────────────────────────┼─────────────────┼─────────────────────┤
76       │993d8d3d-f80e-4225-855a-9daf8ed7ea97 │ Root Partition  │ On Itanium systems, │
77       │                                     │ (Itanium/IA-64) │ the first Itanium   │
78       │                                     │                 │ root partition on   │
79       │                                     │                 │ the disk the EFI    │
80       │                                     │                 │ ESP is located on   │
81       │                                     │                 │ is mounted to the   │
82       │                                     │                 │ root directory /.   │
83       ├─────────────────────────────────────┼─────────────────┼─────────────────────┤
84       │933ac7e1-2eb4-4f13-b844-0e14e2aef915 │ Home Partition  │ The first home      │
85       │                                     │                 │ partition on the    │
86       │                                     │                 │ disk the root       │
87       │                                     │                 │ partition is        │
88       │                                     │                 │ located on is       │
89       │                                     │                 │ mounted to /home.   │
90       ├─────────────────────────────────────┼─────────────────┼─────────────────────┤
91       │3b8f8425-20e0-4f3b-907f-1a25a76f98e8 │ Server Data     │ The first server    │
92       │                                     │ Partition       │ data partition on   │
93       │                                     │                 │ the disk the root   │
94       │                                     │                 │ partition is        │
95       │                                     │                 │ located on is       │
96       │                                     │                 │ mounted to /srv.    │
97       ├─────────────────────────────────────┼─────────────────┼─────────────────────┤
98       │0657fd6d-a4ab-43c4-84e5-0933c84b4f4f │ Swap            │ All swap partitions │
99       │                                     │                 │ located on the disk │
100       │                                     │                 │ the root partition  │
101       │                                     │                 │ is located on are   │
102       │                                     │                 │ enabled.            │
103       ├─────────────────────────────────────┼─────────────────┼─────────────────────┤
104       │c12a7328-f81f-11d2-ba4b-00a0c93ec93b │ EFI System      │ The first ESP       │
105       │                                     │ Partition (ESP) │ located on the disk │
106       │                                     │                 │ the root partition  │
107       │                                     │                 │ is located on is    │
108       │                                     │                 │ mounted to /boot or │
109       │                                     │                 │ /efi, see below.    │
110       └─────────────────────────────────────┴─────────────────┴─────────────────────┘
111
112       This generator understands the following attribute flags for
113       partitions:
114
115       Table 2. Partition Attributes
116       ┌──────────────────────────────┬────────────────────┬────────────────┬──────────────────┐
117Name                          Value              Applicable to  Explanation      
118       ├──────────────────────────────┼────────────────────┼────────────────┼──────────────────┤
119GPT_FLAG_READ_ONLY            │ 0x1000000000000000 │ /, /srv, /home │ Partition is     │
120       │                              │                    │                │ mounted          │
121       │                              │                    │                │ read-only        │
122       ├──────────────────────────────┼────────────────────┼────────────────┼──────────────────┤
123GPT_FLAG_NO_AUTO              │ 0x8000000000000000 │ /, /srv, /home │ Partition is not │
124       │                              │                    │                │ mounted          │
125       │                              │                    │                │ automatically    │
126       ├──────────────────────────────┼────────────────────┼────────────────┼──────────────────┤
127GPT_FLAG_NO_BLOCK_IO_PROTOCOL │ 0x0000000000000002 │ ESP            │ Partition is not │
128       │                              │                    │                │ mounted          │
129       │                              │                    │                │ automatically    │
130       └──────────────────────────────┴────────────────────┴────────────────┴──────────────────┘
131
132       The /home and /srv partitions may be encrypted in LUKS format. In this
133       case, a device mapper device is set up under the names /dev/mapper/home
134       and /dev/mapper/srv. Note that this might create conflicts if the same
135       partition is listed in /etc/crypttab with a different device mapper
136       device name.
137
138       Mount and automount units for the EFI System Partition (ESP) are
139       generated on EFI systems. The ESP is mounted to /boot, unless a mount
140       point directory /efi exists, in which case it is mounted there. Since
141       this generator creates an automount unit, the mount will only be
142       activated on-demand, when accessed. On systems where /boot (or /efi if
143       it exists) is an explicitly configured mount (for example, listed in
144       fstab(5)) or where the /boot (or /efi) mount point is non-empty, no
145       mount units are generated.
146
147       When using this generator in conjunction with btrfs file systems, make
148       sure to set the correct default subvolumes on them, using btrfs
149       subvolume set-default.
150
151       systemd-gpt-auto-generator implements systemd.generator(7).
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SEE ALSO

154       systemd(1), systemd.mount(5), systemd.swap(5), systemd-fstab-
155       generator(8), systemd-cryptsetup@.service(8), cryptsetup(8), fstab(5),
156       btrfs(8)
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NOTES

159        1. UEFI Specification
160           http://www.uefi.org/specifications
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162        2. Discoverable Partitions Specification
163           https://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/
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167systemd 241                                      SYSTEMD-GPT-AUTO-GENERATOR(8)
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