{ "mode": "man", "parameter": "systemd-gpt-auto-generator", "section": "8", "url": "https://www.chedong.com/phpMan.php/man/systemd-gpt-auto-generator/8/json", "generated": "2026-06-16T06:22:50Z", "synopsis": "/lib/systemd/system-generators/systemd-gpt-auto-generator", "sections": { "NAME": { "content": "systemd-gpt-auto-generator - Generator for automatically discovering and mounting root,\n/home/, /srv/, /var/ and /var/tmp/ partitions, as well as discovering and enabling swap\npartitions, based on GPT partition type GUIDs\n", "subsections": [] }, "SYNOPSIS": { "content": "/lib/systemd/system-generators/systemd-gpt-auto-generator\n", "subsections": [] }, "DESCRIPTION": { "content": "systemd-gpt-auto-generator is a unit generator that automatically discovers root, /home/,\n/srv/, /var/, /var/tmp/, the EFI System Partition, the Extended Boot Loader Partition and\nswap partitions and creates mount and swap units for them, based on the partition type GUIDs\nof GUID partition tables (GPT), see UEFI Specification[1], chapter 5. It implements the\nDiscoverable Partitions Specification[2]. Note that this generator has no effect on non-GPT\nsystems, and on specific mount points that are directories already containing files. Also, on\nsystems where the units are explicitly configured (for example, listed in fstab(5)), the\nunits this generator creates are overridden, but additional implicit dependencies might be\ncreated.\n\nThis generator will only look for the root partition on the same physical disk the EFI System\nPartition (ESP) is located on. Note that support from the boot loader is required: the EFI\nvariable LoaderDevicePartUUID of the 4a67b082-0a4c-41cf-b6c7-440b29bb8c4f vendor UUID is used\nto determine from which partition, and hence the disk from which the system was booted. If\nthe boot loader does not set this variable, this generator will not be able to autodetect the\nroot partition. See the Boot Loader Interface[3] for details.\n\nSimilarly, this generator will only look for the other partitions on the same physical disk\nas the root partition. In this case, boot loader support is not required. These partitions\nwill not be searched for on systems where the root file system is distributed on multiple\ndisks, for example via btrfs RAID.\n\nsystemd-gpt-auto-generator is useful for centralizing file system configuration in the\npartition table and making configuration in /etc/fstab or on the kernel command line\nunnecessary.\n\nThis generator looks for the partitions based on their partition type GUID. The following\npartition type GUIDs are identified:\n", "subsections": [ { "name": "Table 1. Partition Type GUIDs", "content": "┌─────────────────────────────────────┬──────────────────────┬─────────────────┬──────────────────────┐\n│Partition Type GUID │ Name │ Mount Point │ Explanation │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│44479540-f297-41b2-9af7-d131d5f0458a │ Root Partition (x86) │ / │ On 32-bit x86 │\n│ │ │ │ systems, the first │\n│ │ │ │ x86 root partition │\n│ │ │ │ on the disk the EFI │\n│ │ │ │ ESP is located on is │\n│ │ │ │ mounted to the root │\n│ │ │ │ directory /. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│4f68bce3-e8cd-4db1-96e7-fbcaf984b709 │ Root Partition │ / │ On 64-bit x86 │\n│ │ (x86-64) │ │ systems, the first │\n│ │ │ │ x86-64 root │\n│ │ │ │ partition on the │\n│ │ │ │ disk the EFI ESP is │\n│ │ │ │ located on is │\n│ │ │ │ mounted to the root │\n│ │ │ │ directory /. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│69dad710-2ce4-4e3c-b16c-21a1d49abed3 │ Root Partition │ / │ On 32-bit ARM │\n│ │ (32-bit ARM) │ │ systems, the first │\n│ │ │ │ ARM root partition │\n│ │ │ │ on the disk the EFI │\n│ │ │ │ ESP is located on is │\n│ │ │ │ mounted to the root │\n│ │ │ │ directory /. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│b921b045-1df0-41c3-af44-4c6f280d3fae │ Root Partition │ / │ On 64-bit ARM │\n│ │ (64-bit ARM) │ │ systems, the first │\n│ │ │ │ ARM root partition │\n│ │ │ │ on the disk the EFI │\n│ │ │ │ ESP is located on is │\n│ │ │ │ mounted to the root │\n│ │ │ │ directory /. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│993d8d3d-f80e-4225-855a-9daf8ed7ea97 │ Root Partition │ / │ On Itanium systems, │\n│ │ (Itanium/IA-64) │ │ the first Itanium │\n│ │ │ │ root partition on │\n│ │ │ │ the disk the EFI ESP │\n│ │ │ │ is located on is │\n│ │ │ │ mounted to the root │\n│ │ │ │ directory /. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│60d5a7fe-8e7d-435c-b714-3dd8162144e1 │ Root Partition │ / │ On RISC-V 32-bit │\n│ │ (RISCV-V 32) │ │ systems, the first │\n│ │ │ │ RISCV-V 32-bit root │\n│ │ │ │ partition on the │\n│ │ │ │ disk the EFI ESP is │\n│ │ │ │ located on is │\n│ │ │ │ mounted to the root │\n│ │ │ │ directory /. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│72ec70a6-cf74-40e6-bd49-4bda08e8f224 │ Root Partition │ / │ On RISC-V 64-bit │\n│ │ (RISCV-V 64) │ │ systems, the first │\n│ │ │ │ RISCV-V 64-bit root │\n│ │ │ │ partition on the │\n│ │ │ │ disk the EFI ESP is │\n│ │ │ │ located on is │\n│ │ │ │ mounted to the root │\n│ │ │ │ directory /. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│933ac7e1-2eb4-4f13-b844-0e14e2aef915 │ Home Partition │ /home/ │ The first home │\n│ │ │ │ partition on the │\n│ │ │ │ disk the root │\n│ │ │ │ partition is located │\n│ │ │ │ on is mounted to │\n│ │ │ │ /home/. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│3b8f8425-20e0-4f3b-907f-1a25a76f98e8 │ Server Data │ /srv/ │ The first server │\n│ │ Partition │ │ data partition on │\n│ │ │ │ the disk the root │\n│ │ │ │ partition is located │\n│ │ │ │ on is mounted to │\n│ │ │ │ /srv/. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│4d21b016-b534-45c2-a9fb-5c16e091fd2d │ Variable Data │ /var/ │ The first variable │\n│ │ Partition │ │ data partition on │\n│ │ │ │ the disk the root │\n│ │ │ │ partition is located │\n│ │ │ │ on is mounted to │\n│ │ │ │ /var/ — under the │\n│ │ │ │ condition its │\n│ │ │ │ partition UUID │\n│ │ │ │ matches the first │\n│ │ │ │ 128 bit of the │\n│ │ │ │ HMAC-SHA256 of the │\n│ │ │ │ GPT type uuid of │\n│ │ │ │ this partition keyed │\n│ │ │ │ by the machine ID of │\n│ │ │ │ the installation │\n│ │ │ │ stored in machine- │\n│ │ │ │ id(5). │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│7ec6f557-3bc5-4aca-b293-16ef5df639d1 │ Temporary Data │ /var/tmp/ │ The first temporary │\n│ │ Partition │ │ data partition on │\n│ │ │ │ the disk the root │\n│ │ │ │ partition is located │\n│ │ │ │ on is mounted to │\n│ │ │ │ /var/tmp/. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│0657fd6d-a4ab-43c4-84e5-0933c84b4f4f │ Swap │ n/a │ All swap partitions │\n│ │ │ │ located on the disk │\n│ │ │ │ the root partition │\n│ │ │ │ is located on are │\n│ │ │ │ enabled. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│c12a7328-f81f-11d2-ba4b-00a0c93ec93b │ EFI System Partition │ /efi/ or /boot/ │ The first ESP │\n│ │ (ESP) │ │ located on the disk │\n│ │ │ │ the root partition │\n│ │ │ │ is located on is │\n│ │ │ │ mounted to /boot/ or │\n│ │ │ │ /efi/, see below. │\n├─────────────────────────────────────┼──────────────────────┼─────────────────┼──────────────────────┤\n│bc13c2ff-59e6-4262-a352-b275fd6f7172 │ Extended Boot Loader │ /boot/ │ The first Extended │\n│ │ Partition │ │ Boot Loader │\n│ │ │ │ Partition is mounted │\n│ │ │ │ to /boot/, see │\n│ │ │ │ below. │\n└─────────────────────────────────────┴──────────────────────┴─────────────────┴──────────────────────┘\n\nThis generator understands the following attribute flags for partitions:\n" }, { "name": "Table 2. Partition Attributes", "content": "┌──────────────────────────────┬────────────────────┬──────────────────────┬──────────────────────┐\n│Name │ Value │ Applicable to │ Explanation │\n├──────────────────────────────┼────────────────────┼──────────────────────┼──────────────────────┤\n│GPTFLAGREADONLY │ 0x1000000000000000 │ /, /home/, /srv/, │ Partition is mounted │\n│ │ │ /var/, /var/tmp/, │ read-only │\n│ │ │ Extended Boot Loader │ │\n│ │ │ Partition │ │\n├──────────────────────────────┼────────────────────┼──────────────────────┼──────────────────────┤\n│GPTFLAGNOAUTO │ 0x8000000000000000 │ /, /home/, /srv/, │ Partition is not │\n│ │ │ /var/, /var/tmp/, │ mounted │\n│ │ │ Extended Boot Loader │ automatically │\n│ │ │ Partition │ │\n├──────────────────────────────┼────────────────────┼──────────────────────┼──────────────────────┤\n│GPTFLAGNOBLOCKIOPROTOCOL │ 0x0000000000000002 │ EFI System Partition │ Partition is not │\n│ │ │ (ESP) │ mounted │\n│ │ │ │ automatically │\n└──────────────────────────────┴────────────────────┴──────────────────────┴──────────────────────┘\n\nThe /home/, /srv/, /var/ and /var/tmp/ partitions may be encrypted in LUKS format. In this\ncase, a device mapper device is set up under the names /dev/mapper/home, /dev/mapper/srv,\n/dev/mapper/var and /dev/mapper/tmp. Note that this might create conflicts if the same\npartition is listed in /etc/crypttab with a different device mapper device name.\n\nWhen systemd is running in the initrd the / partition may be encrypted in LUKS format as\nwell. In this case, a device mapper device is set up under the name /dev/mapper/root, and a\nsysroot.mount is set up that mounts the device under /sysroot. For more information, see\nbootup(7).\n\nMount and automount units for the EFI System Partition (ESP) are generated on EFI systems.\nThe ESP is mounted to /boot/ (except if an Extended Boot Loader partition exists, see below),\nunless a mount point directory /efi/ exists, in which case it is mounted there. Since this\ngenerator creates an automount unit, the mount will only be activated on-demand, when\naccessed. On systems where /boot/ (or /efi/ if it exists) is an explicitly configured mount\n(for example, listed in fstab(5)) or where the /boot/ (or /efi/) mount point is non-empty, no\nmount units are generated.\n\nIf the disk contains an Extended Boot Loader partition, as defined in the Boot Loader\nSpecification[4], it is made available at /boot/ (by means of an automount point, similar to\nthe ESP, see above). If both an EFI System Partition and an Extended Boot Loader partition\nexist the latter is preferably mounted to /boot/. Make sure to create both /efi/ and /boot/\nto ensure both partitions are mounted.\n\nWhen using this generator in conjunction with btrfs file systems, make sure to set the\ncorrect default subvolumes on them, using btrfs subvolume set-default.\n\nsystemd-gpt-auto-generator implements systemd.generator(7).\n" } ] }, "KERNEL COMMAND LINE": { "content": "systemd-gpt-auto-generator understands the following kernel command line parameters:\n\nsystemd.gptauto, rd.systemd.gptauto\nThose options take an optional boolean argument, and default to yes. The generator is\nenabled by default, and a negative value may be used to disable it.\n\nroot=\nWhen used with the special value \"gpt-auto\", automatic discovery of the root partition\nbased on the GPT partition type is enabled. Any other value disables this generator.\n\nrw, ro\nMount the root partition read-write or read-only initially.\n\nNote that unlike most kernel command line options these settings do not override\nconfiguration in the file system, and the file system may be remounted later. See\nsystemd-remount-fs.service(8).\n", "subsections": [] }, "SEE ALSO": { "content": "systemd(1), systemd.mount(5), systemd.swap(5), systemd-fstab-generator(8), systemd-\ncryptsetup@.service(8), machine-id(5), cryptsetup(8), fstab(5), btrfs(8)\n", "subsections": [] }, "NOTES": { "content": "1. UEFI Specification\nhttps://uefi.org/specifications\n\n2. Discoverable Partitions Specification\nhttps://systemd.io/DISCOVERABLEPARTITIONS\n\n3. Boot Loader Interface\nhttps://systemd.io/BOOTLOADERINTERFACE\n\n4. Boot Loader Specification\nhttps://systemd.io/BOOTLOADERSPECIFICATION\n\n\n\nsystemd 249 SYSTEMD-GPT-AUTO-GENERATOR(8)", "subsections": [] } }, "summary": "systemd-gpt-auto-generator - Generator for automatically discovering and mounting root, /home/, /srv/, /var/ and /var/tmp/ partitions, as well as discovering and enabling swap partitions, based on GPT partition type GUIDs", "flags": [], "examples": [], "see_also": [ { "name": "systemd", "section": "1", "url": "https://www.chedong.com/phpMan.php/man/systemd/1/json" }, { "name": "systemd.mount", "section": "5", "url": "https://www.chedong.com/phpMan.php/man/systemd.mount/5/json" }, { "name": "systemd.swap", "section": "5", "url": "https://www.chedong.com/phpMan.php/man/systemd.swap/5/json" }, { "name": "systemd-fstab-generator", "section": "8", "url": "https://www.chedong.com/phpMan.php/man/systemd-fstab-generator/8/json" }, { "name": ".service", "section": "8", "url": "https://www.chedong.com/phpMan.php/man/.service/8/json" }, { "name": "machine-id", "section": "5", "url": "https://www.chedong.com/phpMan.php/man/machine-id/5/json" }, { "name": "cryptsetup", "section": "8", "url": "https://www.chedong.com/phpMan.php/man/cryptsetup/8/json" }, { "name": "fstab", "section": "5", "url": "https://www.chedong.com/phpMan.php/man/fstab/5/json" }, { "name": "btrfs", "section": "8", "url": "https://www.chedong.com/phpMan.php/man/btrfs/8/json" } ] }