{
    "mode": "man",
    "parameter": "fstab",
    "section": "5",
    "url": "https://www.chedong.com/phpMan.php/man/fstab/5/json",
    "generated": "2026-06-02T17:54:25Z",
    "synopsis": "/etc/fstab",
    "sections": {
        "NAME": {
            "content": "fstab - static information about the filesystems\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "/etc/fstab\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "The file fstab contains descriptive information about the filesystems the system can mount.\nfstab is only read by programs, and not written; it is the duty of the system administrator\nto properly create and maintain this file. The order of records in fstab is important because\nfsck(8), mount(8), and umount(8) sequentially iterate through fstab doing their thing.\n\nEach filesystem is described on a separate line. Fields on each line are separated by tabs or\nspaces. Lines starting with '#' are comments. Blank lines are ignored.\n\nThe following is a typical example of an fstab entry:\n\nLABEL=t-home2   /home      ext4    defaults,autodaalloc      0  2\n\nThe first field (fsspec).\nThis field describes the block special device, remote filesystem or filesystem image for loop\ndevice to be mounted or swap file or swap partition to be enabled.\n\nFor ordinary mounts, it will hold (a link to) a block special device node (as created by\nmknod(2)) for the device to be mounted, like /dev/cdrom or /dev/sdb7. For NFS mounts, this\nfield is <host>:<dir>, e.g., knuth.aeb.nl:/. For filesystems with no storage, any string can\nbe used, and will show up in df(1) output, for example. Typical usage is proc for procfs;\nmem, none, or tmpfs for tmpfs. Other special filesystems, like udev and sysfs, are typically\nnot listed in fstab.\n\nLABEL=<label> or UUID=<uuid> may be given instead of a device name. This is the recommended\nmethod, as device names are often a coincidence of hardware detection order, and can change\nwhen other disks are added or removed. For example, 'LABEL=Boot' or\n'UUID=3e6be9de-8139-11d1-9106-a43f08d823a6'. (Use a filesystem-specific tool like e2label(8),\nxfsadmin(8), or fatlabel(8) to set LABELs on filesystems).\n\nIt’s also possible to use PARTUUID= and PARTLABEL=. These partitions identifiers are\nsupported for example for GUID Partition Table (GPT).\n\nSee mount(8), blkid(8) or lsblk(8) for more details about device identifiers.\n\nNote that mount(8) uses UUIDs as strings. The string representation of the UUID should be\nbased on lower case characters. But when specifying the volume ID of FAT or NTFS file systems\nupper case characters are used (e.g UUID=\"A40D-85E7\" or UUID=\"61DB7756DB7779B3\").\n\nThe second field (fsfile).\nThis field describes the mount point (target) for the filesystem. For swap partitions, this\nfield should be specified as `none'. If the name of the mount point contains spaces or tabs\nthese can be escaped as `\\040' and '\\011' respectively.\n\nThe third field (fsvfstype).\nThis field describes the type of the filesystem. Linux supports many filesystem types: ext4,\nxfs, btrfs, f2fs, vfat, ntfs, hfsplus, tmpfs, sysfs, proc, iso9660, udf, squashfs, nfs, cifs,\nand many more. For more details, see mount(8).\n\nAn entry swap denotes a file or partition to be used for swapping, cf. swapon(8). An entry\nnone is useful for bind or move mounts.\n\nMore than one type may be specified in a comma-separated list.\n\nmount(8) and umount(8) support filesystem subtypes. The subtype is defined by '.subtype'\nsuffix. For example 'fuse.sshfs'. It’s recommended to use subtype notation rather than add\nany prefix to the first fstab field (for example 'sshfs#example.com' is deprecated).\n\nThe fourth field (fsmntops).\nThis field describes the mount options associated with the filesystem.\n\nIt is formatted as a comma-separated list of options. It contains at least the type of mount\n(ro or rw), plus any additional options appropriate to the filesystem type (including\nperformance-tuning options). For details, see mount(8) or swapon(8).\n\nBasic filesystem-independent options are:\n",
            "subsections": [
                {
                    "name": "defaults",
                    "content": "use default options: rw, suid, dev, exec, auto, nouser, and async.\n"
                },
                {
                    "name": "noauto",
                    "content": "do not mount when mount -a is given (e.g., at boot time)\n"
                },
                {
                    "name": "user",
                    "content": "allow a user to mount\n"
                },
                {
                    "name": "owner",
                    "content": "allow device owner to mount\n"
                },
                {
                    "name": "comment",
                    "content": "or x-<name> for use by fstab-maintaining programs\n"
                },
                {
                    "name": "nofail",
                    "content": "do not report errors for this device if it does not exist.\n\nThe fifth field (fsfreq).\nThis field is used by dump(8) to determine which filesystems need to be dumped. Defaults to\nzero (don’t dump) if not present.\n\nThe sixth field (fspassno).\nThis field is used by fsck(8) to determine the order in which filesystem checks are done at\nboot time. The root filesystem should be specified with a fspassno of 1. Other filesystems\nshould have a fspassno of 2. Filesystems within a drive will be checked sequentially, but\nfilesystems on different drives will be checked at the same time to utilize parallelism\navailable in the hardware. Defaults to zero (don’t check the filesystem) if not present.\n"
                }
            ]
        },
        "FILES": {
            "content": "/etc/fstab, <fstab.h>\n",
            "subsections": []
        },
        "NOTES": {
            "content": "The proper way to read records from fstab is to use the routines getmntent(3) or libmount.\n\nThe keyword ignore as a filesystem type (3rd field) is no longer supported by the pure\nlibmount based mount utility (since util-linux v2.22).\n",
            "subsections": []
        },
        "HISTORY": {
            "content": "The ancestor of this fstab file format appeared in 4.0BSD.\n",
            "subsections": []
        },
        "SEE ALSO": {
            "content": "getmntent(3), fs(5), findmnt(8), mount(8), swapon(8)\n",
            "subsections": []
        },
        "REPORTING BUGS": {
            "content": "For bug reports, use the issue tracker at https://github.com/karelzak/util-linux/issues.\n",
            "subsections": []
        },
        "AVAILABILITY": {
            "content": "fstab is part of the util-linux package which can be downloaded from Linux Kernel Archive\n<https://www.kernel.org/pub/linux/utils/util-linux/>.\n\n\n\nutil-linux 2.37.2                            2021-06-02                                     FSTAB(5)",
            "subsections": []
        }
    },
    "summary": "fstab - static information about the filesystems",
    "flags": [],
    "examples": [],
    "see_also": [
        {
            "name": "getmntent",
            "section": "3",
            "url": "https://www.chedong.com/phpMan.php/man/getmntent/3/json"
        },
        {
            "name": "fs",
            "section": "5",
            "url": "https://www.chedong.com/phpMan.php/man/fs/5/json"
        },
        {
            "name": "findmnt",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/findmnt/8/json"
        },
        {
            "name": "mount",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/mount/8/json"
        },
        {
            "name": "swapon",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/swapon/8/json"
        }
    ]
}