{
    "mode": "man",
    "parameter": "mount",
    "section": "8",
    "url": "https://www.chedong.com/phpMan.php/man/mount/8/json",
    "generated": "2026-06-13T20:00:36Z",
    "synopsis": "mount [-h|-V]\nmount [-l] [-t fstype]\nmount -a [-fFnrsvw] [-t fstype] [-O optlist]\nmount [-fnrsvw] [-o options] device|mountpoint\nmount [-fnrsvw] [-t fstype] [-o options] device mountpoint\nmount --bind|--rbind|--move olddir newdir\nmount --make-[shared|slave|private|unbindable|rshared|rslave|rprivate|runbindable] mountpoint",
    "sections": {
        "NAME": {
            "content": "mount - mount a filesystem\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "mount [-h|-V]\n\nmount [-l] [-t fstype]\n\nmount -a [-fFnrsvw] [-t fstype] [-O optlist]\n\nmount [-fnrsvw] [-o options] device|mountpoint\n\nmount [-fnrsvw] [-t fstype] [-o options] device mountpoint\n\nmount --bind|--rbind|--move olddir newdir\n\nmount --make-[shared|slave|private|unbindable|rshared|rslave|rprivate|runbindable] mountpoint\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "All files accessible in a Unix system are arranged in one big tree, the file hierarchy,\nrooted at /. These files can be spread out over several devices. The mount command serves to\nattach the filesystem found on some device to the big file tree. Conversely, the umount(8)\ncommand will detach it again. The filesystem is used to control how data is stored on the\ndevice or provided in a virtual way by network or other services.\n\nThe standard form of the mount command is:\n\nmount -t type device dir\n\nThis tells the kernel to attach the filesystem found on device (which is of type type) at the\ndirectory dir. The option -t type is optional. The mount command is usually able to detect a\nfilesystem. The root permissions are necessary to mount a filesystem by default. See section\n\"Non-superuser mounts\" below for more details. The previous contents (if any) and owner and\nmode of dir become invisible, and as long as this filesystem remains mounted, the pathname\ndir refers to the root of the filesystem on device.\n\nIf only the directory or the device is given, for example:\n\nmount /dir\n\nthen mount looks for a mountpoint (and if not found then for a device) in the /etc/fstab\nfile. It’s possible to use the --target or --source options to avoid ambiguous interpretation\nof the given argument. For example:\n\nmount --target /mountpoint\n\nThe same filesystem may be mounted more than once, and in some cases (e.g., network\nfilesystems) the same filesystem may be mounted on the same mountpoint multiple times. The\nmount command does not implement any policy to control this behavior. All behavior is\ncontrolled by the kernel and it is usually specific to the filesystem driver. The exception\nis --all, in this case already mounted filesystems are ignored (see --all below for more\ndetails).\n",
            "subsections": [
                {
                    "name": "Listing the mounts",
                    "content": "The listing mode is maintained for backward compatibility only.\n\nFor more robust and customizable output use findmnt(8), especially in your scripts. Note that\ncontrol characters in the mountpoint name are replaced with '?'.\n\nThe following command lists all mounted filesystems (of type type):\n\nmount [-l] [-t type]\n\nThe option -l adds labels to this listing. See below.\n"
                },
                {
                    "name": "Indicating the device and filesystem",
                    "content": "Most devices are indicated by a filename (of a block special device), like /dev/sda1, but\nthere are other possibilities. For example, in the case of an NFS mount, device may look like\nknuth.cwi.nl:/dir.\n\nThe device names of disk partitions are unstable; hardware reconfiguration, and adding or\nremoving a device can cause changes in names. This is the reason why it’s strongly\nrecommended to use filesystem or partition identifiers like UUID or LABEL. Currently\nsupported identifiers (tags):\n\nLABEL=label\nHuman readable filesystem identifier. See also -L.\n\nUUID=uuid\nFilesystem universally unique identifier. The format of the UUID is usually a series of\nhex digits separated by hyphens. See also -U.\n\nNote that mount uses UUIDs as strings. The UUIDs from the command line or from fstab(5)\nare not converted to internal binary representation. The string representation of the\nUUID should be based on lower case characters.\n\nPARTLABEL=label\nHuman readable partition identifier. This identifier is independent on filesystem and\ndoes not change by mkfs or mkswap operations It’s supported for example for GUID\nPartition Tables (GPT).\n\nPARTUUID=uuid\nPartition universally unique identifier. This identifier is independent on filesystem and\ndoes not change by mkfs or mkswap operations It’s supported for example for GUID\nPartition Tables (GPT).\n\nID=id\nHardware block device ID as generated by udevd. This identifier is usually based on WWN\n(unique storage identifier) and assigned by the hardware manufacturer. See ls\n/dev/disk/by-id for more details, this directory and running udevd is required. This\nidentifier is not recommended for generic use as the identifier is not strictly defined\nand it depends on udev, udev rules and hardware.\n\nThe command lsblk --fs provides an overview of filesystems, LABELs and UUIDs on available\nblock devices. The command blkid -p <device> provides details about a filesystem on the\nspecified device.\n\nDon’t forget that there is no guarantee that UUIDs and labels are really unique, especially\nif you move, share or copy the device. Use lsblk -o +UUID,PARTUUID to verify that the UUIDs\nare really unique in your system.\n\nThe recommended setup is to use tags (e.g. UUID=uuid) rather than\n/dev/disk/by-{label,uuid,id,partuuid,partlabel} udev symlinks in the /etc/fstab file. Tags\nare more readable, robust and portable. The mount(8) command internally uses udev symlinks,\nso the use of symlinks in /etc/fstab has no advantage over tags. For more details see\nlibblkid(3).\n\nThe proc filesystem is not associated with a special device, and when mounting it, an\narbitrary keyword - for example, proc - can be used instead of a device specification. (The\ncustomary choice none is less fortunate: the error message 'none already mounted' from mount\ncan be confusing.)\n"
                },
                {
                    "name": "The files /etc/fstab, /etc/mtab and /proc/mounts",
                    "content": "The file /etc/fstab (see fstab(5)), may contain lines describing what devices are usually\nmounted where, using which options. The default location of the fstab(5) file can be\noverridden with the --fstab path command-line option (see below for more details).\n\nThe command\n\nmount -a [-t type] [-O optlist]\n\n(usually given in a bootscript) causes all filesystems mentioned in fstab (of the proper type\nand/or having or not having the proper options) to be mounted as indicated, except for those\nwhose line contains the noauto keyword. Adding the -F option will make mount fork, so that\nthe filesystems are mounted in parallel.\n\nWhen mounting a filesystem mentioned in fstab or mtab, it suffices to specify on the command\nline only the device, or only the mount point.\n\nThe programs mount and umount(8) traditionally maintained a list of currently mounted\nfilesystems in the file /etc/mtab. The support for regular classic /etc/mtab is completely\ndisabled at compile time by default, because on current Linux systems it is better to make\n/etc/mtab a symlink to /proc/mounts instead. The regular mtab file maintained in userspace\ncannot reliably work with namespaces, containers and other advanced Linux features. If the\nregular mtab support is enabled, then it’s possible to use the file as well as the symlink.\n\nIf no arguments are given to mount, the list of mounted filesystems is printed.\n\nIf you want to override mount options from /etc/fstab, you have to use the -o option:\n\nmount device|dir -o options\n\nand then the mount options from the command line will be appended to the list of options from\n/etc/fstab. This default behaviour can be changed using the --options-mode command-line\noption. The usual behavior is that the last option wins if there are conflicting ones.\n\nThe mount program does not read the /etc/fstab file if both device (or LABEL, UUID, ID,\nPARTUUID or PARTLABEL) and dir are specified. For example, to mount device foo at /dir:\n\nmount /dev/foo /dir\n\nThis default behaviour can be changed by using the --options-source-force command-line option\nto always read configuration from fstab. For non-root users mount always reads the fstab\nconfiguration.\n"
                },
                {
                    "name": "Non-superuser mounts",
                    "content": "Normally, only the superuser can mount filesystems. However, when fstab contains the user\noption on a line, anybody can mount the corresponding filesystem.\n\nThus, given a line\n\n/dev/cdrom /cd iso9660 ro,user,noauto,unhide\n\nany user can mount the iso9660 filesystem found on an inserted CDROM using the command:\n\nmount /cd\n\nNote that mount is very strict about non-root users and all paths specified on command line\nare verified before fstab is parsed or a helper program is executed. It’s strongly\nrecommended to use a valid mountpoint to specify filesystem, otherwise mount may fail. For\nexample it’s a bad idea to use NFS or CIFS source on command line.\n\nSince util-linux 2.35, mount does not exit when user permissions are inadequate according to\nlibmount’s internal security rules. Instead, it drops suid permissions and continues as\nregular non-root user. This behavior supports use-cases where root permissions are not\nnecessary (e.g., fuse filesystems, user namespaces, etc).\n\nFor more details, see fstab(5). Only the user that mounted a filesystem can unmount it again.\nIf any user should be able to unmount it, then use users instead of user in the fstab line.\nThe owner option is similar to the user option, with the restriction that the user must be\nthe owner of the special file. This may be useful e.g. for /dev/fd if a login script makes\nthe console user owner of this device. The group option is similar, with the restriction that\nthe user must be a member of the group of the special file.\n"
                },
                {
                    "name": "Bind mount operation",
                    "content": "Remount part of the file hierarchy somewhere else. The call is:\n\nmount --bind olddir newdir\n\nor by using this fstab entry:\n\n/olddir /newdir none bind\n\nAfter this call the same contents are accessible in two places.\n\nIt is important to understand that \"bind\" does not create any second-class or special node in\nthe kernel VFS. The \"bind\" is just another operation to attach a filesystem. There is nowhere\nstored information that the filesystem has been attached by a \"bind\" operation. The olddir\nand newdir are independent and the olddir may be unmounted.\n\nOne can also remount a single file (on a single file). It’s also possible to use a bind mount\nto create a mountpoint from a regular directory, for example:\n\nmount --bind foo foo\n\nThe bind mount call attaches only (part of) a single filesystem, not possible submounts. The\nentire file hierarchy including submounts can be attached a second place by using:\n\nmount --rbind olddir newdir\n\nNote that the filesystem mount options maintained by the kernel will remain the same as those\non the original mount point. The userspace mount options (e.g., netdev) will not be copied\nby mount and it’s necessary to explicitly specify the options on the mount command line.\n\nSince util-linux 2.27 mount permits changing the mount options by passing the relevant\noptions along with --bind. For example:\n\nmount -o bind,ro foo foo\n\nThis feature is not supported by the Linux kernel; it is implemented in userspace by an\nadditional mount(2) remounting system call. This solution is not atomic.\n\nThe alternative (classic) way to create a read-only bind mount is to use the remount\noperation, for example:\n\nmount --bind olddir newdir mount -o remount,bind,ro olddir newdir\n\nNote that a read-only bind will create a read-only mountpoint (VFS entry), but the original\nfilesystem superblock will still be writable, meaning that the olddir will be writable, but\nthe newdir will be read-only.\n\nIt’s also possible to change nosuid, nodev, noexec, noatime, nodiratime and relatime VFS\nentry flags via a \"remount,bind\" operation. The other flags (for example filesystem-specific\nflags) are silently ignored. It’s impossible to change mount options recursively (for example\nwith -o rbind,ro).\n\nSince util-linux 2.31, mount ignores the bind flag from /etc/fstab on a remount operation (if\n\"-o remount\" is specified on command line). This is necessary to fully control mount options\non remount by command line. In previous versions the bind flag has been always applied and it\nwas impossible to re-define mount options without interaction with the bind semantic. This\nmount behavior does not affect situations when \"remount,bind\" is specified in the /etc/fstab\nfile.\n"
                },
                {
                    "name": "The move operation",
                    "content": "Move a mounted tree to another place (atomically). The call is:\n\nmount --move olddir newdir\n\nThis will cause the contents which previously appeared under olddir to now be accessible\nunder newdir. The physical location of the files is not changed. Note that olddir has to be a\nmountpoint.\n\nNote also that moving a mount residing under a shared mount is invalid and unsupported. Use\nfindmnt -o TARGET,PROPAGATION to see the current propagation flags.\n"
                },
                {
                    "name": "Shared subtree operations",
                    "content": "Since Linux 2.6.15 it is possible to mark a mount and its submounts as shared, private, slave\nor unbindable. A shared mount provides the ability to create mirrors of that mount such that\nmounts and unmounts within any of the mirrors propagate to the other mirror. A slave mount\nreceives propagation from its master, but not vice versa. A private mount carries no\npropagation abilities. An unbindable mount is a private mount which cannot be cloned through\na bind operation. The detailed semantics are documented in\nDocumentation/filesystems/sharedsubtree.txt file in the kernel source tree; see also\nmountnamespaces(7).\n\nSupported operations are:\n\nmount --make-shared mountpoint\nmount --make-slave mountpoint\nmount --make-private mountpoint\nmount --make-unbindable mountpoint\n\nThe following commands allow one to recursively change the type of all the mounts under a\ngiven mountpoint.\n\nmount --make-rshared mountpoint\nmount --make-rslave mountpoint\nmount --make-rprivate mountpoint\nmount --make-runbindable mountpoint\n\nmount(8) does not read fstab(5) when a --make-* operation is requested. All necessary\ninformation has to be specified on the command line.\n\nNote that the Linux kernel does not allow changing multiple propagation flags with a single\nmount(2) system call, and the flags cannot be mixed with other mount options and operations.\n\nSince util-linux 2.23 the mount command can be used to do more propagation (topology) changes\nby one mount(8) call and do it also together with other mount operations. The propagation\nflags are applied by additional mount(2) system calls when the preceding mount operations\nwere successful. Note that this use case is not atomic. It is possible to specify the\npropagation flags in fstab(5) as mount options (private, slave, shared, unbindable, rprivate,\nrslave, rshared, runbindable).\n\nFor example:\n\nmount --make-private --make-unbindable /dev/sda1 /foo\n\nis the same as:\n\nmount /dev/sda1 /foo\nmount --make-private /foo\nmount --make-unbindable /foo\n"
                }
            ]
        },
        "COMMAND-LINE OPTIONS": {
            "content": "The full set of mount options used by an invocation of mount is determined by first\nextracting the mount options for the filesystem from the fstab table, then applying any\noptions specified by the -o argument, and finally applying a -r or -w option, when present.\n\nThe mount command does not pass all command-line options to the /sbin/mount.suffix mount\nhelpers. The interface between mount and the mount helpers is described below in the section\nEXTERNAL HELPERS.\n\nCommand-line options available for the mount command are:\n",
            "subsections": [
                {
                    "name": "-a --all",
                    "content": "Mount all filesystems (of the given types) mentioned in fstab (except for those whose\nline contains the noauto keyword). The filesystems are mounted following their order in\nfstab. The mount command compares filesystem source, target (and fs root for bind mount\nor btrfs) to detect already mounted filesystems. The kernel table with already mounted\nfilesystems is cached during mount --all. This means that all duplicated fstab entries\nwill be mounted.\n\nThe option --all is possible to use for remount operation too. In this case all filters\n(-t and -O) are applied to the table of already mounted filesystems.\n\nSince version 2.35 is possible to use the command line option -o to alter mount options\nfrom fstab (see also --options-mode).\n\nNote that it is a bad practice to use mount -a for fstab checking. The recommended\nsolution is findmnt --verify.\n",
                    "flag": "-a",
                    "long": "--all"
                },
                {
                    "name": "-B --bind",
                    "content": "Remount a subtree somewhere else (so that its contents are available in both places). See\nabove, under Bind mounts.\n",
                    "flag": "-B",
                    "long": "--bind"
                },
                {
                    "name": "-c --no-canonicalize",
                    "content": "Don’t canonicalize paths. The mount command canonicalizes all paths (from the command\nline or fstab) by default. This option can be used together with the -f flag for already\ncanonicalized absolute paths. The option is designed for mount helpers which call mount\n-i. It is strongly recommended to not use this command-line option for normal mount\noperations.\n\nNote that mount does not pass this option to the /sbin/mount.type helpers.\n",
                    "flag": "-c",
                    "long": "--no-canonicalize"
                },
                {
                    "name": "-F --fork",
                    "content": "(Used in conjunction with -a.) Fork off a new incarnation of mount for each device. This\nwill do the mounts on different devices or different NFS servers in parallel. This has\nthe advantage that it is faster; also NFS timeouts proceed in parallel. A disadvantage is\nthat the order of the mount operations is undefined. Thus, you cannot use this option if\nyou want to mount both /usr and /usr/spool.\n",
                    "flag": "-F",
                    "long": "--fork"
                },
                {
                    "name": "-f, --fake",
                    "content": "Causes everything to be done except for the actual system call; if it’s not obvious, this\n\"fakes\" mounting the filesystem. This option is useful in conjunction with the -v flag to\ndetermine what the mount command is trying to do. It can also be used to add entries for\ndevices that were mounted earlier with the -n option. The -f option checks for an\nexisting record in /etc/mtab and fails when the record already exists (with a regular\nnon-fake mount, this check is done by the kernel).\n",
                    "flag": "-f",
                    "long": "--fake"
                },
                {
                    "name": "-i, --internal-only",
                    "content": "Don’t call the /sbin/mount.filesystem helper even if it exists.\n",
                    "flag": "-i",
                    "long": "--internal-only"
                },
                {
                    "name": "-L --label",
                    "content": "Mount the partition that has the specified label.\n",
                    "flag": "-L",
                    "long": "--label"
                },
                {
                    "name": "-l --show-labels",
                    "content": "Add the labels in the mount output. mount must have permission to read the disk device\n(e.g. be set-user-ID root) for this to work. One can set such a label for ext2, ext3 or\next4 using the e2label(8) utility, or for XFS using xfsadmin(8), or for reiserfs using\nreiserfstune(8).\n",
                    "flag": "-l",
                    "long": "--show-labels"
                },
                {
                    "name": "-M --move",
                    "content": "Move a subtree to some other place. See above, the subsection The move operation.\n",
                    "flag": "-M",
                    "long": "--move"
                },
                {
                    "name": "-n --no-mtab",
                    "content": "Mount without writing in /etc/mtab. This is necessary for example when /etc is on a\nread-only filesystem.\n",
                    "flag": "-n",
                    "long": "--no-mtab"
                },
                {
                    "name": "-N --namespace",
                    "content": "Perform the mount operation in the mount namespace specified by ns. ns is either PID of\nprocess running in that namespace or special file representing that namespace.\n\nmount switches to the mount namespace when it reads /etc/fstab, writes /etc/mtab: (or\nwrites to /run/mount) and calls the mount(2) system call, otherwise it runs in the\noriginal mount namespace. This means that the target namespace does not have to contain\nany libraries or other requirements necessary to execute the mount(2) call.\n\nSee mountnamespaces(7) for more information.\n",
                    "flag": "-N",
                    "long": "--namespace"
                },
                {
                    "name": "-O --test-opts",
                    "content": "Limit the set of filesystems to which the -a option applies. In this regard it is like\nthe -t option except that -O is useless without -a. For example, the command\n\nmount -a -O nonetdev\n\nmounts all filesystems except those which have the option netdev specified in the options\nfield in the /etc/fstab file.\n\nIt is different from -t in that each option is matched exactly; a leading no at the\nbeginning of one option does not negate the rest.\n\nThe -t and -O options are cumulative in effect; that is, the command\n\nmount -a -t ext2 -O  netdev\n\nmounts all ext2 filesystems with the netdev option, not all filesystems that are either\next2 or have the netdev option specified.\n",
                    "flag": "-O",
                    "long": "--test-opts"
                },
                {
                    "name": "-o --options",
                    "content": "Use the specified mount options. The opts argument is a comma-separated list. For\nexample:\n\nmount LABEL=mydisk -o noatime,nodev,nosuid\n\nFor more details, see the FILESYSTEM-INDEPENDENT MOUNT OPTIONS and FILESYSTEM-SPECIFIC\nMOUNT OPTIONS sections.\n\n--options-mode mode\nControls how to combine options from fstab/mtab with options from the command line. mode\ncan be one of ignore, append, prepend or replace. For example, append means that options\nfrom fstab are appended to options from the command line. The default value is prepend —\nit means command line options are evaluated after fstab options. Note that the last\noption wins if there are conflicting ones.\n\n--options-source source\nSource of default options. source is a comma-separated list of fstab, mtab and disable.\ndisable disables fstab and mtab and disables --options-source-force. The default value is\nfstab,mtab.\n",
                    "flag": "-o",
                    "long": "--options"
                },
                {
                    "name": "--options-source-force",
                    "content": "Use options from fstab/mtab even if both device and dir are specified.\n",
                    "long": "--options-source-force"
                },
                {
                    "name": "-R --rbind",
                    "content": "Remount a subtree and all possible submounts somewhere else (so that its contents are\navailable in both places). See above, the subsection Bind mounts.\n",
                    "flag": "-R",
                    "long": "--rbind"
                },
                {
                    "name": "-r --read-only",
                    "content": "Mount the filesystem read-only. A synonym is -o ro.\n\nNote that, depending on the filesystem type, state and kernel behavior, the system may\nstill write to the device. For example, ext3 and ext4 will replay the journal if the\nfilesystem is dirty. To prevent this kind of write access, you may want to mount an ext3\nor ext4 filesystem with the ro,noload mount options or set the block device itself to\nread-only mode, see the blockdev(8) command.\n",
                    "flag": "-r",
                    "long": "--read-only"
                },
                {
                    "name": "-s",
                    "content": "Tolerate sloppy mount options rather than failing. This will ignore mount options not\nsupported by a filesystem type. Not all filesystems support this option. Currently it’s\nsupported by the mount.nfs mount helper only.\n\n--source device\nIf only one argument for the mount command is given, then the argument might be\ninterpreted as the target (mountpoint) or source (device). This option allows you to\nexplicitly define that the argument is the mount source.\n\n--target directory\nIf only one argument for the mount command is given, then the argument might be\ninterpreted as the target (mountpoint) or source (device). This option allows you to\nexplicitly define that the argument is the mount target.\n\n--target-prefix directory\nPrepend the specified directory to all mount targets. This option can be used to follow\nfstab, but mount operations are done in another place, for example:\n\nmount --all --target-prefix /chroot -o X-mount.mkdir\n\nmounts all from system fstab to /chroot, all missing mountpoint are created (due to\nX-mount.mkdir). See also --fstab to use an alternative fstab.\n",
                    "flag": "-s"
                },
                {
                    "name": "-T --fstab",
                    "content": "Specifies an alternative fstab file. If path is a directory, then the files in the\ndirectory are sorted by strverscmp(3); files that start with \".\" or without an .fstab\nextension are ignored. The option can be specified more than once. This option is mostly\ndesigned for initramfs or chroot scripts where additional configuration is specified\nbeyond standard system configuration.\n\nNote that mount does not pass the option --fstab to the /sbin/mount.type helpers, meaning\nthat the alternative fstab files will be invisible for the helpers. This is no problem\nfor normal mounts, but user (non-root) mounts always require fstab to verify the user’s\nrights.\n",
                    "flag": "-T",
                    "long": "--fstab"
                },
                {
                    "name": "-t --types",
                    "content": "The argument following the -t is used to indicate the filesystem type. The filesystem\ntypes which are currently supported depend on the running kernel. See /proc/filesystems\nand /lib/modules/$(uname -r)/kernel/fs for a complete list of the filesystems. The most\ncommon are ext2, ext3, ext4, xfs, btrfs, vfat, sysfs, proc, nfs and cifs.\n\nThe programs mount and umount(8) support filesystem subtypes. The subtype is defined by a\n'.subtype' suffix. For example 'fuse.sshfs'. It’s recommended to use subtype notation\nrather than add any prefix to the mount source (for example 'sshfs#example.com' is\ndeprecated).\n\nIf no -t option is given, or if the auto type is specified, mount will try to guess the\ndesired type. mount uses the libblkid(3) library for guessing the filesystem type; if\nthat does not turn up anything that looks familiar, mount will try to read the file\n/etc/filesystems, or, if that does not exist, /proc/filesystems. All of the filesystem\ntypes listed there will be tried, except for those that are labeled \"nodev\" (e.g. devpts,\nproc and nfs). If /etc/filesystems ends in a line with a single *, mount will read\n/proc/filesystems afterwards. While trying, all filesystem types will be mounted with the\nmount option silent.\n\nThe auto type may be useful for user-mounted floppies. Creating a file /etc/filesystems\ncan be useful to change the probe order (e.g., to try vfat before msdos or ext3 before\next2) or if you use a kernel module autoloader.\n\nMore than one type may be specified in a comma-separated list, for the -t option as well\nas in an /etc/fstab entry. The list of filesystem types for the -t option can be prefixed\nwith no to specify the filesystem types on which no action should be taken. The prefix no\nhas no effect when specified in an /etc/fstab entry.\n\nThe prefix no can be meaningful with the -a option. For example, the command\n\nmount -a -t nomsdos,smbfs\n\nmounts all filesystems except those of type msdos and smbfs.\n\nFor most types all the mount program has to do is issue a simple mount(2) system call,\nand no detailed knowledge of the filesystem type is required. For a few types however\n(like nfs, nfs4, cifs, smbfs, ncpfs) an ad hoc code is necessary. The nfs, nfs4, cifs,\nsmbfs, and ncpfs filesystems have a separate mount program. In order to make it possible\nto treat all types in a uniform way, mount will execute the program /sbin/mount.type (if\nthat exists) when called with type type. Since different versions of the smbmount program\nhave different calling conventions, /sbin/mount.smbfs may have to be a shell script that\nsets up the desired call.\n",
                    "flag": "-t",
                    "long": "--types"
                },
                {
                    "name": "-U --uuid",
                    "content": "Mount the partition that has the specified uuid.\n",
                    "flag": "-U",
                    "long": "--uuid"
                },
                {
                    "name": "-v --verbose",
                    "content": "Verbose mode.\n",
                    "flag": "-v",
                    "long": "--verbose"
                },
                {
                    "name": "-w --rw --read-write",
                    "content": "Mount the filesystem read/write. Read-write is the kernel default and the mount default\nis to try read-only if the previous mount syscall with read-write flags on\nwrite-protected devices of filesystems failed.\n\nA synonym is -o rw.\n\nNote that specifying -w on the command line forces mount to never try read-only mount on\nwrite-protected devices or already mounted read-only filesystems.\n",
                    "flag": "-w",
                    "long": "--read-write"
                },
                {
                    "name": "-V --version",
                    "content": "Display version information and exit.\n",
                    "flag": "-V",
                    "long": "--version"
                },
                {
                    "name": "-h --help",
                    "content": "Display help text and exit.\n",
                    "flag": "-h",
                    "long": "--help"
                }
            ]
        },
        "FILESYSTEM-INDEPENDENT MOUNT OPTIONS": {
            "content": "Some of these options are only useful when they appear in the /etc/fstab file.\n\nSome of these options could be enabled or disabled by default in the system kernel. To check\nthe current setting see the options in /proc/mounts. Note that filesystems also have\nper-filesystem specific default mount options (see for example tune2fs -l output for extN\nfilesystems).\n\nThe following options apply to any filesystem that is being mounted (but not every filesystem\nactually honors them - e.g., the sync option today has an effect only for ext2, ext3, ext4,\nfat, vfat, ufs and xfs):\n",
            "subsections": [
                {
                    "name": "async",
                    "content": "All I/O to the filesystem should be done asynchronously. (See also the sync option.)\n"
                },
                {
                    "name": "atime",
                    "content": "Do not use the noatime feature, so the inode access time is controlled by kernel\ndefaults. See also the descriptions of the relatime and strictatime mount options.\n"
                },
                {
                    "name": "noatime",
                    "content": "Do not update inode access times on this filesystem (e.g. for faster access on the news\nspool to speed up news servers). This works for all inode types (directories too), so it\nimplies nodiratime.\n"
                },
                {
                    "name": "auto",
                    "content": "Can be mounted with the -a option.\n"
                },
                {
                    "name": "noauto",
                    "content": "Can only be mounted explicitly (i.e., the -a option will not cause the filesystem to be\nmounted).\n\ncontext=context, fscontext=context, defcontext=context, and rootcontext=context\nThe context= option is useful when mounting filesystems that do not support extended\nattributes, such as a floppy or hard disk formatted with VFAT, or systems that are not\nnormally running under SELinux, such as an ext3 or ext4 formatted disk from a non-SELinux\nworkstation. You can also use context= on filesystems you do not trust, such as a floppy.\nIt also helps in compatibility with xattr-supporting filesystems on earlier 2.4.<x>\nkernel versions. Even where xattrs are supported, you can save time not having to label\nevery file by assigning the entire disk one security context.\n\nA commonly used option for removable media is context=\"systemu:objectr:removablet.\n\nThe fscontext= option works for all filesystems, regardless of their xattr support. The\nfscontext option sets the overarching filesystem label to a specific security context.\nThis filesystem label is separate from the individual labels on the files. It represents\nthe entire filesystem for certain kinds of permission checks, such as during mount or\nfile creation. Individual file labels are still obtained from the xattrs on the files\nthemselves. The context option actually sets the aggregate context that fscontext\nprovides, in addition to supplying the same label for individual files.\n\nYou can set the default security context for unlabeled files using defcontext= option.\nThis overrides the value set for unlabeled files in the policy and requires a filesystem\nthat supports xattr labeling.\n\nThe rootcontext= option allows you to explicitly label the root inode of a FS being\nmounted before that FS or inode becomes visible to userspace. This was found to be useful\nfor things like stateless Linux.\n\nNote that the kernel rejects any remount request that includes the context option, even\nwhen unchanged from the current context.\n\nWarning: the context value might contain commas, in which case the value has to be\nproperly quoted, otherwise mount will interpret the comma as a separator between mount\noptions. Don’t forget that the shell strips off quotes and thus double quoting is\nrequired. For example:\n\nmount -t tmpfs none /mnt -o \\\n'context=\"systemu:objectr:tmpt:s0:c127,c456\",noexec'\n\nFor more details, see selinux(8).\n"
                },
                {
                    "name": "defaults",
                    "content": "Use the default options: rw, suid, dev, exec, auto, nouser, and async.\n\nNote that the real set of all default mount options depends on the kernel and filesystem\ntype. See the beginning of this section for more details.\n"
                },
                {
                    "name": "dev",
                    "content": "Interpret character or block special devices on the filesystem.\n"
                },
                {
                    "name": "nodev",
                    "content": "Do not interpret character or block special devices on the filesystem.\n"
                },
                {
                    "name": "diratime",
                    "content": "Update directory inode access times on this filesystem. This is the default. (This option\nis ignored when noatime is set.)\n"
                },
                {
                    "name": "nodiratime",
                    "content": "Do not update directory inode access times on this filesystem. (This option is implied\nwhen noatime is set.)\n"
                },
                {
                    "name": "dirsync",
                    "content": "All directory updates within the filesystem should be done synchronously. This affects\nthe following system calls: creat(2), link(2), unlink(2), symlink(2), mkdir(2), rmdir(2),\nmknod(2) and rename(2).\n"
                },
                {
                    "name": "exec",
                    "content": "Permit execution of binaries.\n"
                },
                {
                    "name": "noexec",
                    "content": "Do not permit direct execution of any binaries on the mounted filesystem.\n"
                },
                {
                    "name": "group",
                    "content": "Allow an ordinary user to mount the filesystem if one of that user’s groups matches the\ngroup of the device. This option implies the options nosuid and nodev (unless overridden\nby subsequent options, as in the option line group,dev,suid).\n"
                },
                {
                    "name": "iversion",
                    "content": "Every time the inode is modified, the iversion field will be incremented.\n"
                },
                {
                    "name": "noiversion",
                    "content": "Do not increment the iversion inode field.\n"
                },
                {
                    "name": "mand",
                    "content": "Allow mandatory locks on this filesystem. See fcntl(2).\n"
                },
                {
                    "name": "nomand",
                    "content": "Do not allow mandatory locks on this filesystem.\n\nnetdev\nThe filesystem resides on a device that requires network access (used to prevent the\nsystem from attempting to mount these filesystems until the network has been enabled on\nthe system).\n"
                },
                {
                    "name": "nofail",
                    "content": "Do not report errors for this device if it does not exist.\n"
                },
                {
                    "name": "relatime",
                    "content": "Update inode access times relative to modify or change time. Access time is only updated\nif the previous access time was earlier than the current modify or change time. (Similar\nto noatime, but it doesn’t break mutt(1) or other applications that need to know if a\nfile has been read since the last time it was modified.)\n\nSince Linux 2.6.30, the kernel defaults to the behavior provided by this option (unless\nnoatime was specified), and the strictatime option is required to obtain traditional\nsemantics. In addition, since Linux 2.6.30, the file’s last access time is always updated\nif it is more than 1 day old.\n"
                },
                {
                    "name": "norelatime",
                    "content": "Do not use the relatime feature. See also the strictatime mount option.\n"
                },
                {
                    "name": "strictatime",
                    "content": "Allows to explicitly request full atime updates. This makes it possible for the kernel to\ndefault to relatime or noatime but still allow userspace to override it. For more details\nabout the default system mount options see /proc/mounts.\n"
                },
                {
                    "name": "nostrictatime",
                    "content": "Use the kernel’s default behavior for inode access time updates.\n"
                },
                {
                    "name": "lazytime",
                    "content": "Only update times (atime, mtime, ctime) on the in-memory version of the file inode.\n\nThis mount option significantly reduces writes to the inode table for workloads that\nperform frequent random writes to preallocated files.\n\nThe on-disk timestamps are updated only when:\n\n•   the inode needs to be updated for some change unrelated to file timestamps\n\n•   the application employs fsync(2), syncfs(2), or sync(2)\n\n•   an undeleted inode is evicted from memory\n\n•   more than 24 hours have passed since the inode was written to disk.\n"
                },
                {
                    "name": "nolazytime",
                    "content": "Do not use the lazytime feature.\n"
                },
                {
                    "name": "suid",
                    "content": "Honor set-user-ID and set-group-ID bits or file capabilities when executing programs from\nthis filesystem.\n"
                },
                {
                    "name": "nosuid",
                    "content": "Do not honor set-user-ID and set-group-ID bits or file capabilities when executing\nprograms from this filesystem. In addition, SELinux domain transitions require permission\nnosuidtransition, which in turn needs also policy capability nnpnosuidtransition.\n"
                },
                {
                    "name": "silent",
                    "content": "Turn on the silent flag.\n"
                },
                {
                    "name": "loud",
                    "content": "Turn off the silent flag.\n"
                },
                {
                    "name": "owner",
                    "content": "Allow an ordinary user to mount the filesystem if that user is the owner of the device.\nThis option implies the options nosuid and nodev (unless overridden by subsequent\noptions, as in the option line owner,dev,suid).\n"
                },
                {
                    "name": "remount",
                    "content": "Attempt to remount an already-mounted filesystem. This is commonly used to change the\nmount flags for a filesystem, especially to make a readonly filesystem writable. It does\nnot change device or mount point.\n\nThe remount operation together with the bind flag has special semantics. See above, the\nsubsection Bind mounts.\n\nThe remount functionality follows the standard way the mount command works with options\nfrom fstab. This means that mount does not read fstab (or mtab) only when both device and\ndir are specified.\n\nmount -o remount,rw /dev/foo /dir\n\nAfter this call all old mount options are replaced and arbitrary stuff from fstab (or\nmtab) is ignored, except the loop= option which is internally generated and maintained by\nthe mount command.\n\nmount -o remount,rw /dir\n\nAfter this call, mount reads fstab and merges these options with the options from the\ncommand line (-o). If no mountpoint is found in fstab, then a remount with unspecified\nsource is allowed.\n\nmount allows the use of --all to remount all already mounted filesystems which match a\nspecified filter (-O and -t). For example:\n\nmount --all -o remount,ro -t vfat\n\nremounts all already mounted vfat filesystems in read-only mode. Each of the filesystems\nis remounted by mount -o remount,ro /dir semantic. This means the mount command reads\nfstab or mtab and merges these options with the options from the command line.\n\nro\nMount the filesystem read-only.\n\nrw\nMount the filesystem read-write.\n"
                },
                {
                    "name": "sync",
                    "content": "All I/O to the filesystem should be done synchronously. In the case of media with a\nlimited number of write cycles (e.g. some flash drives), sync may cause life-cycle\nshortening.\n"
                },
                {
                    "name": "user",
                    "content": "Allow an ordinary user to mount the filesystem. The name of the mounting user is written\nto the mtab file (or to the private libmount file in /run/mount on systems without a\nregular mtab) so that this same user can unmount the filesystem again. This option\nimplies the options noexec, nosuid, and nodev (unless overridden by subsequent options,\nas in the option line user,exec,dev,suid).\n"
                },
                {
                    "name": "nouser",
                    "content": "Forbid an ordinary user to mount the filesystem. This is the default; it does not imply\nany other options.\n"
                },
                {
                    "name": "users",
                    "content": "Allow any user to mount and to unmount the filesystem, even when some other ordinary user\nmounted it. This option implies the options noexec, nosuid, and nodev (unless overridden\nby subsequent options, as in the option line users,exec,dev,suid).\n\nX-*\nAll options prefixed with \"X-\" are interpreted as comments or as userspace\napplication-specific options. These options are not stored in user space (e.g., mtab\nfile), nor sent to the mount.type helpers nor to the mount(2) system call. The suggested\nformat is X-appname.option.\n\nx-*\nThe same as X-* options, but stored permanently in user space. This means the options are\nalso available for umount(8) or other operations. Note that maintaining mount options in\nuser space is tricky, because it’s necessary use libmount-based tools and there is no\nguarantee that the options will be always available (for example after a move mount\noperation or in unshared namespace).\n\nNote that before util-linux v2.30 the x-* options have not been maintained by libmount\nand stored in user space (functionality was the same as for X-* now), but due to the\ngrowing number of use-cases (in initrd, systemd etc.) the functionality has been extended\nto keep existing fstab configurations usable without a change.\n\nX-mount.mkdir[=mode]\nAllow to make a target directory (mountpoint) if it does not exit yet. The optional\nargument mode specifies the filesystem access mode used for mkdir(2) in octal notation.\nThe default mode is 0755. This functionality is supported only for root users or when\nmount executed without suid permissions. The option is also supported as x-mount.mkdir,\nthis notation is deprecated since v2.30.\n"
                },
                {
                    "name": "nosymfollow",
                    "content": "Do not follow symlinks when resolving paths. Symlinks can still be created, and\nreadlink(1), readlink(2), realpath(1), and realpath(3) all still work properly.\n"
                }
            ]
        },
        "FILESYSTEM-SPECIFIC MOUNT OPTIONS": {
            "content": "This section lists options that are specific to particular filesystems. Where possible, you\nshould first consult filesystem-specific manual pages for details. Some of those pages are\nlisted in the following table.\n\n┌─────────────────┬───────────────┐\n│                 │               │\n│Filesystem(s)    │ Manual page   │\n├─────────────────┼───────────────┤\n│                 │               │\n│btrfs            │ btrfs(5)      │\n├─────────────────┼───────────────┤\n│                 │               │\n│cifs             │ mount.cifs(8) │\n├─────────────────┼───────────────┤\n│                 │               │\n│ext2, ext3, ext4 │ ext4(5)       │\n├─────────────────┼───────────────┤\n│                 │               │\n│fuse             │ fuse(8)       │\n├─────────────────┼───────────────┤\n│                 │               │\n│nfs              │ nfs(5)        │\n├─────────────────┼───────────────┤\n│                 │               │\n│tmpfs            │ tmpfs(5)      │\n├─────────────────┼───────────────┤\n│                 │               │\n│xfs              │ xfs(5)        │\n└─────────────────┴───────────────┘\n\nNote that some of the pages listed above might be available only after you install the\nrespective userland tools.\n\nThe following options apply only to certain filesystems. We sort them by filesystem. All\noptions follow the -o flag.\n\nWhat options are supported depends a bit on the running kernel. Further information may be\navailable in filesystem-specific files in the kernel source subdirectory\nDocumentation/filesystems.\n",
            "subsections": [
                {
                    "name": "Mount options for adfs",
                    "content": "uid=value and gid=value\nSet the owner and group of the files in the filesystem (default: uid=gid=0).\n\nownmask=value and othmask=value\nSet the permission mask for ADFS 'owner' permissions and 'other' permissions,\nrespectively (default: 0700 and 0077, respectively). See also\n/usr/src/linux/Documentation/filesystems/adfs.rst.\n"
                },
                {
                    "name": "Mount options for affs",
                    "content": "uid=value and gid=value\nSet the owner and group of the root of the filesystem (default: uid=gid=0, but with\noption uid or gid without specified value, the UID and GID of the current process are\ntaken).\n\nsetuid=value and setgid=value\nSet the owner and group of all files.\n\nmode=value\nSet the mode of all files to value & 0777 disregarding the original permissions. Add\nsearch permission to directories that have read permission. The value is given in octal.\n"
                },
                {
                    "name": "protect",
                    "content": "Do not allow any changes to the protection bits on the filesystem.\n"
                },
                {
                    "name": "usemp",
                    "content": "Set UID and GID of the root of the filesystem to the UID and GID of the mount point upon\nthe first sync or umount, and then clear this option. Strange...\n"
                },
                {
                    "name": "verbose",
                    "content": "Print an informational message for each successful mount.\n\nprefix=string\nPrefix used before volume name, when following a link.\n\nvolume=string\nPrefix (of length at most 30) used before '/' when following a symbolic link.\n\nreserved=value\n(Default: 2.) Number of unused blocks at the start of the device.\n\nroot=value\nGive explicitly the location of the root block.\n\nbs=value\nGive blocksize. Allowed values are 512, 1024, 2048, 4096.\n\ngrpquota|noquota|quota|usrquota\nThese options are accepted but ignored. (However, quota utilities may react to such\nstrings in /etc/fstab.)\n"
                },
                {
                    "name": "Mount options for debugfs",
                    "content": "The debugfs filesystem is a pseudo filesystem, traditionally mounted on /sys/kernel/debug. As\nof kernel version 3.4, debugfs has the following options:\n\nuid=n, gid=n\nSet the owner and group of the mountpoint.\n\nmode=value\nSets the mode of the mountpoint.\n"
                },
                {
                    "name": "Mount options for devpts",
                    "content": "The devpts filesystem is a pseudo filesystem, traditionally mounted on /dev/pts. In order to\nacquire a pseudo terminal, a process opens /dev/ptmx; the number of the pseudo terminal is\nthen made available to the process and the pseudo terminal slave can be accessed as\n/dev/pts/<number>.\n\nuid=value and gid=value\nThis sets the owner or the group of newly created pseudo terminals to the specified\nvalues. When nothing is specified, they will be set to the UID and GID of the creating\nprocess. For example, if there is a tty group with GID 5, then gid=5 will cause newly\ncreated pseudo terminals to belong to the tty group.\n\nmode=value\nSet the mode of newly created pseudo terminals to the specified value. The default is\n0600. A value of mode=620 and gid=5 makes \"mesg y\" the default on newly created pseudo\nterminals.\n"
                },
                {
                    "name": "newinstance",
                    "content": "Create a private instance of the devpts filesystem, such that indices of pseudo terminals\nallocated in this new instance are independent of indices created in other instances of\ndevpts.\n\nAll mounts of devpts without this newinstance option share the same set of pseudo\nterminal indices (i.e., legacy mode). Each mount of devpts with the newinstance option\nhas a private set of pseudo terminal indices.\n\nThis option is mainly used to support containers in the Linux kernel. It is implemented\nin Linux kernel versions starting with 2.6.29. Further, this mount option is valid only\nif CONFIGDEVPTSMULTIPLEINSTANCES is enabled in the kernel configuration.\n\nTo use this option effectively, /dev/ptmx must be a symbolic link to pts/ptmx. See\nDocumentation/filesystems/devpts.txt in the Linux kernel source tree for details.\n\nptmxmode=value\nSet the mode for the new ptmx device node in the devpts filesystem.\n\nWith the support for multiple instances of devpts (see newinstance option above), each\ninstance has a private ptmx node in the root of the devpts filesystem (typically\n/dev/pts/ptmx).\n\nFor compatibility with older versions of the kernel, the default mode of the new ptmx\nnode is 0000. ptmxmode=value specifies a more useful mode for the ptmx node and is highly\nrecommended when the newinstance option is specified.\n\nThis option is only implemented in Linux kernel versions starting with 2.6.29. Further,\nthis option is valid only if CONFIGDEVPTSMULTIPLEINSTANCES is enabled in the kernel\nconfiguration.\n"
                },
                {
                    "name": "Mount options for fat",
                    "content": "(Note: fat is not a separate filesystem, but a common part of the msdos, umsdos and vfat\nfilesystems.)\n\nblocksize={512|1024|2048}\nSet blocksize (default 512). This option is obsolete.\n\nuid=value and gid=value\nSet the owner and group of all files. (Default: the UID and GID of the current process.)\n\numask=value\nSet the umask (the bitmask of the permissions that are not present). The default is the\numask of the current process. The value is given in octal.\n\ndmask=value\nSet the umask applied to directories only. The default is the umask of the current\nprocess. The value is given in octal.\n\nfmask=value\nSet the umask applied to regular files only. The default is the umask of the current\nprocess. The value is given in octal.\n\nallowutime=value\nThis option controls the permission check of mtime/atime.\n\n20\nIf current process is in group of file’s group ID, you can change timestamp.\n\n2\nOther users can change timestamp.\n\nThe default is set from 'dmask' option. (If the directory is writable, utime(2) is also\nallowed. I.e. ~dmask & 022)\n\nNormally utime(2) checks that the current process is owner of the file, or that it has the\nCAPFOWNER capability. But FAT filesystems don’t have UID/GID on disk, so the normal check is\ntoo inflexible. With this option you can relax it.\n\ncheck=value\nThree different levels of pickiness can be chosen:\n\nr[elaxed]\nUpper and lower case are accepted and equivalent, long name parts are truncated (e.g.\nverylongname.foobar becomes verylong.foo), leading and embedded spaces are accepted\nin each name part (name and extension).\n\nn[ormal]\nLike \"relaxed\", but many special characters (*, ?, <, spaces, etc.) are rejected.\nThis is the default.\n\ns[trict]\nLike \"normal\", but names that contain long parts or special characters that are\nsometimes used on Linux but are not accepted by MS-DOS (+, =, etc.) are rejected.\n\ncodepage=value\nSets the codepage for converting to shortname characters on FAT and VFAT filesystems. By\ndefault, codepage 437 is used.\n\nconv=mode\nThis option is obsolete and may fail or be ignored.\n\ncvfformat=module\nForces the driver to use the CVF (Compressed Volume File) module cvfmodule instead of\nauto-detection. If the kernel supports kmod, the cvfformat=xxx option also controls\non-demand CVF module loading. This option is obsolete.\n\ncvfoption=option\nOption passed to the CVF module. This option is obsolete.\n"
                },
                {
                    "name": "debug",
                    "content": "Turn on the debug flag. A version string and a list of filesystem parameters will be\nprinted (these data are also printed if the parameters appear to be inconsistent).\n"
                },
                {
                    "name": "discard",
                    "content": "If set, causes discard/TRIM commands to be issued to the block device when blocks are\nfreed. This is useful for SSD devices and sparse/thinly-provisioned LUNs.\n"
                },
                {
                    "name": "dos1xfloppy",
                    "content": "If set, use a fallback default BIOS Parameter Block configuration, determined by backing\ndevice size. These static parameters match defaults assumed by DOS 1.x for 160 kiB, 180\nkiB, 320 kiB, and 360 kiB floppies and floppy images.\n\nerrors={panic|continue|remount-ro}\nSpecify FAT behavior on critical errors: panic, continue without doing anything, or\nremount the partition in read-only mode (default behavior).\n\nfat={12|16|32}\nSpecify a 12, 16 or 32 bit fat. This overrides the automatic FAT type detection routine.\nUse with caution!\n\niocharset=value\nCharacter set to use for converting between 8 bit characters and 16 bit Unicode\ncharacters. The default is iso8859-1. Long filenames are stored on disk in Unicode\nformat.\n\nnfs={stalerw|nostalero}\nEnable this only if you want to export the FAT filesystem over NFS.\n\nstalerw: This option maintains an index (cache) of directory inodes which is used by the\nnfs-related code to improve look-ups. Full file operations (read/write) over NFS are\nsupported but with cache eviction at NFS server, this could result in spurious ESTALE\nerrors.\n\nnostalero: This option bases the inode number and file handle on the on-disk location of\na file in the FAT directory entry. This ensures that ESTALE will not be returned after a\nfile is evicted from the inode cache. However, it means that operations such as rename,\ncreate and unlink could cause file handles that previously pointed at one file to point\nat a different file, potentially causing data corruption. For this reason, this option\nalso mounts the filesystem readonly.\n\nTo maintain backward compatibility, -o nfs is also accepted, defaulting to stalerw.\n"
                },
                {
                    "name": "tz=UTC",
                    "content": "This option disables the conversion of timestamps between local time (as used by Windows\non FAT) and UTC (which Linux uses internally). This is particularly useful when mounting\ndevices (like digital cameras) that are set to UTC in order to avoid the pitfalls of\nlocal time.\n\ntimeoffset=minutes\nSet offset for conversion of timestamps from local time used by FAT to UTC. I.e., minutes\nwill be subtracted from each timestamp to convert it to UTC used internally by Linux.\nThis is useful when the time zone set in the kernel via settimeofday(2) is not the time\nzone used by the filesystem. Note that this option still does not provide correct time\nstamps in all cases in presence of DST - time stamps in a different DST setting will be\noff by one hour.\n"
                },
                {
                    "name": "quiet",
                    "content": "Turn on the quiet flag. Attempts to chown or chmod files do not return errors, although\nthey fail. Use with caution!\n"
                },
                {
                    "name": "rodir",
                    "content": "FAT has the ATTRRO (read-only) attribute. On Windows, the ATTRRO of the directory will\njust be ignored, and is used only by applications as a flag (e.g. it’s set for the\ncustomized folder).\n\nIf you want to use ATTRRO as read-only flag even for the directory, set this option.\n"
                },
                {
                    "name": "showexec",
                    "content": "If set, the execute permission bits of the file will be allowed only if the extension\npart of the name is .EXE, .COM, or .BAT. Not set by default.\n\nsysimmutable\nIf set, ATTRSYS attribute on FAT is handled as IMMUTABLE flag on Linux. Not set by\ndefault.\n"
                },
                {
                    "name": "flush",
                    "content": "If set, the filesystem will try to flush to disk more early than normal. Not set by\ndefault.\n"
                },
                {
                    "name": "usefree",
                    "content": "Use the \"free clusters\" value stored on FSINFO. It’ll be used to determine number of free\nclusters without scanning disk. But it’s not used by default, because recent Windows\ndon’t update it correctly in some case. If you are sure the \"free clusters\" on FSINFO is\ncorrect, by this option you can avoid scanning disk.\n\ndots, nodots, dotsOK=[yes|no]\nVarious misguided attempts to force Unix or DOS conventions onto a FAT filesystem.\n"
                },
                {
                    "name": "Mount options for hfs",
                    "content": "creator=cccc, type=cccc\nSet the creator/type values as shown by the MacOS finder used for creating new files.\nDefault values: '????'.\n\nuid=n, gid=n\nSet the owner and group of all files. (Default: the UID and GID of the current process.)\n\ndirumask=n, fileumask=n, umask=n\nSet the umask used for all directories, all regular files, or all files and directories.\nDefaults to the umask of the current process.\n\nsession=n\nSelect the CDROM session to mount. Defaults to leaving that decision to the CDROM driver.\nThis option will fail with anything but a CDROM as underlying device.\n\npart=n\nSelect partition number n from the device. Only makes sense for CDROMs. Defaults to not\nparsing the partition table at all.\n"
                },
                {
                    "name": "quiet",
                    "content": "Don’t complain about invalid mount options.\n"
                },
                {
                    "name": "Mount options for hpfs",
                    "content": "uid=value and gid=value\nSet the owner and group of all files. (Default: the UID and GID of the current process.)\n\numask=value\nSet the umask (the bitmask of the permissions that are not present). The default is the\numask of the current process. The value is given in octal.\n\ncase={lower|asis}\nConvert all files names to lower case, or leave them. (Default: case=lower.)\n\nconv=mode\nThis option is obsolete and may fail or being ignored.\n"
                },
                {
                    "name": "nocheck",
                    "content": "Do not abort mounting when certain consistency checks fail.\n"
                },
                {
                    "name": "Mount options for iso9660",
                    "content": "ISO 9660 is a standard describing a filesystem structure to be used on CD-ROMs. (This\nfilesystem type is also seen on some DVDs. See also the udf filesystem.)\n\nNormal iso9660 filenames appear in an 8.3 format (i.e., DOS-like restrictions on filename\nlength), and in addition all characters are in upper case. Also there is no field for file\nownership, protection, number of links, provision for block/character devices, etc.\n\nRock Ridge is an extension to iso9660 that provides all of these UNIX-like features.\nBasically there are extensions to each directory record that supply all of the additional\ninformation, and when Rock Ridge is in use, the filesystem is indistinguishable from a normal\nUNIX filesystem (except that it is read-only, of course).\n"
                },
                {
                    "name": "norock",
                    "content": "Disable the use of Rock Ridge extensions, even if available. Cf. map.\n"
                },
                {
                    "name": "nojoliet",
                    "content": "Disable the use of Microsoft Joliet extensions, even if available. Cf. map.\n\ncheck={r[elaxed]|s[trict]}\nWith check=relaxed, a filename is first converted to lower case before doing the lookup.\nThis is probably only meaningful together with norock and map=normal. (Default:\ncheck=strict.)\n\nuid=value and gid=value\nGive all files in the filesystem the indicated user or group id, possibly overriding the\ninformation found in the Rock Ridge extensions. (Default: uid=0,gid=0.)\n\nmap={n[ormal]|o[ff]|a[corn]}\nFor non-Rock Ridge volumes, normal name translation maps upper to lower case ASCII, drops\na trailing ';1', and converts ';' to '.'. With map=off no name translation is done. See\nnorock. (Default: map=normal.) map=acorn is like map=normal but also apply Acorn\nextensions if present.\n\nmode=value\nFor non-Rock Ridge volumes, give all files the indicated mode. (Default: read and execute\npermission for everybody.) Octal mode values require a leading 0.\n"
                },
                {
                    "name": "unhide",
                    "content": "Also show hidden and associated files. (If the ordinary files and the associated or\nhidden files have the same filenames, this may make the ordinary files inaccessible.)\n\nblock={512|1024|2048}\nSet the block size to the indicated value. (Default: block=1024.)\n\nconv=mode\nThis option is obsolete and may fail or being ignored.\n"
                },
                {
                    "name": "cruft",
                    "content": "If the high byte of the file length contains other garbage, set this mount option to\nignore the high order bits of the file length. This implies that a file cannot be larger\nthan 16 MB.\n\nsession=x\nSelect number of session on a multisession CD.\n\nsbsector=xxx\nSession begins from sector xxx.\n\nThe following options are the same as for vfat and specifying them only makes sense when\nusing discs encoded using Microsoft’s Joliet extensions.\n\niocharset=value\nCharacter set to use for converting 16 bit Unicode characters on CD to 8 bit characters.\nThe default is iso8859-1.\n"
                },
                {
                    "name": "utf8",
                    "content": "Convert 16 bit Unicode characters on CD to UTF-8.\n"
                },
                {
                    "name": "Mount options for jfs",
                    "content": "iocharset=name\nCharacter set to use for converting from Unicode to ASCII. The default is to do no\nconversion. Use iocharset=utf8 for UTF8 translations. This requires CONFIGNLSUTF8 to be\nset in the kernel .config file.\n\nresize=value\nResize the volume to value blocks. JFS only supports growing a volume, not shrinking it.\nThis option is only valid during a remount, when the volume is mounted read-write. The\nresize keyword with no value will grow the volume to the full size of the partition.\n"
                },
                {
                    "name": "nointegrity",
                    "content": "Do not write to the journal. The primary use of this option is to allow for higher\nperformance when restoring a volume from backup media. The integrity of the volume is not\nguaranteed if the system abnormally ends.\n"
                },
                {
                    "name": "integrity",
                    "content": "Default. Commit metadata changes to the journal. Use this option to remount a volume\nwhere the nointegrity option was previously specified in order to restore normal\nbehavior.\n\nerrors={continue|remount-ro|panic}\nDefine the behavior when an error is encountered. (Either ignore errors and just mark the\nfilesystem erroneous and continue, or remount the filesystem read-only, or panic and halt\nthe system.)\n\nnoquota|quota|usrquota|grpquota\nThese options are accepted but ignored.\n"
                },
                {
                    "name": "Mount options for msdos",
                    "content": "See mount options for fat. If the msdos filesystem detects an inconsistency, it reports an\nerror and sets the file system read-only. The filesystem can be made writable again by\nremounting it.\n"
                },
                {
                    "name": "Mount options for ncpfs",
                    "content": "Just like nfs, the ncpfs implementation expects a binary argument (a struct ncpmountdata)\nto the mount system call. This argument is constructed by ncpmount(8) and the current version\nof mount (2.12) does not know anything about ncpfs.\n"
                },
                {
                    "name": "Mount options for ntfs",
                    "content": "iocharset=name\nCharacter set to use when returning file names. Unlike VFAT, NTFS suppresses names that\ncontain nonconvertible characters. Deprecated.\n\nnls=name\nNew name for the option earlier called iocharset.\n"
                },
                {
                    "name": "utf8",
                    "content": "Use UTF-8 for converting file names.\n\nunixlate={0|1|2}\nFor 0 (or 'no' or 'false'), do not use escape sequences for unknown Unicode characters.\nFor 1 (or 'yes' or 'true') or 2, use vfat-style 4-byte escape sequences starting with\n\":\". Here 2 gives a little-endian encoding and 1 a byteswapped bigendian encoding.\n"
                },
                {
                    "name": "posix=[0|1]",
                    "content": "If enabled (posix=1), the filesystem distinguishes between upper and lower case. The 8.3\nalias names are presented as hard links instead of being suppressed. This option is\nobsolete.\n\nuid=value, gid=value and umask=value\nSet the file permission on the filesystem. The umask value is given in octal. By default,\nthe files are owned by root and not readable by somebody else.\n"
                },
                {
                    "name": "Mount options for overlay",
                    "content": "Since Linux 3.18 the overlay pseudo filesystem implements a union mount for other\nfilesystems.\n\nAn overlay filesystem combines two filesystems - an upper filesystem and a lower filesystem.\nWhen a name exists in both filesystems, the object in the upper filesystem is visible while\nthe object in the lower filesystem is either hidden or, in the case of directories, merged\nwith the upper object.\n\nThe lower filesystem can be any filesystem supported by Linux and does not need to be\nwritable. The lower filesystem can even be another overlayfs. The upper filesystem will\nnormally be writable and if it is it must support the creation of trusted.* extended\nattributes, and must provide a valid dtype in readdir responses, so NFS is not suitable.\n\nA read-only overlay of two read-only filesystems may use any filesystem type. The options\nlowerdir and upperdir are combined into a merged directory by using:\n\nmount -t overlay  overlay  \\\n-olowerdir=/lower,upperdir=/upper,workdir=/work  /merged\n\nlowerdir=directory\nAny filesystem, does not need to be on a writable filesystem.\n\nupperdir=directory\nThe upperdir is normally on a writable filesystem.\n\nworkdir=directory\nThe workdir needs to be an empty directory on the same filesystem as upperdir.\n"
                },
                {
                    "name": "userxattr",
                    "content": "Use the \"user.overlay.\" xattr namespace instead of \"trusted.overlay.\". This is useful for\nunprivileged mounting of overlayfs.\n\nredirectdir={on|off|follow|nofollow}\nIf the redirectdir feature is enabled, then the directory will be copied up (but not the\ncontents). Then the \"{trusted|user}.overlay.redirect\" extended attribute is set to the\npath of the original location from the root of the overlay. Finally the directory is\nmoved to the new location.\n\non\nRedirects are enabled.\n\noff\nRedirects are not created and only followed if \"redirectalwaysfollow\" feature is\nenabled in the kernel/module config.\n\nfollow\nRedirects are not created, but followed.\n\nnofollow\nRedirects are not created and not followed (equivalent to \"redirectdir=off\" if\n\"redirectalwaysfollow\" feature is not enabled).\n\nindex={on|off}\nInode index. If this feature is disabled and a file with multiple hard links is copied\nup, then this will \"break\" the link. Changes will not be propagated to other names\nreferring to the same inode.\n\nuuid={on|off}\nCan be used to replace UUID of the underlying filesystem in file handles with null, and\neffectively disable UUID checks. This can be useful in case the underlying disk is copied\nand the UUID of this copy is changed. This is only applicable if all lower/upper/work\ndirectories are on the same filesystem, otherwise it will fallback to normal behaviour.\n\nnfsexport={on|off}\nWhen the underlying filesystems supports NFS export and the \"nfsexport\" feature is\nenabled, an overlay filesystem may be exported to NFS.\n\nWith the “nfsexport” feature, on copyup of any lower object, an index entry is created\nunder the index directory. The index entry name is the hexadecimal representation of the\ncopy up origin file handle. For a non-directory object, the index entry is a hard link to\nthe upper inode. For a directory object, the index entry has an extended attribute\n\"{trusted|user}.overlay.upper\" with an encoded file handle of the upper directory inode.\n\nWhen encoding a file handle from an overlay filesystem object, the following rules apply\n\n•   For a non-upper object, encode a lower file handle from lower inode\n\n•   For an indexed object, encode a lower file handle from copyup origin\n\n•   For a pure-upper object and for an existing non-indexed upper object, encode an\nupper file handle from upper inode\n\nThe encoded overlay file handle includes\n\n•   Header including path type information (e.g. lower/upper)\n\n•   UUID of the underlying filesystem\n\n•   Underlying filesystem encoding of underlying inode\n\nThis encoding format is identical to the encoding format file handles that are stored in\nextended attribute \"{trusted|user}.overlay.origin\". When decoding an overlay file handle,\nthe following steps are followed\n\n•   Find underlying layer by UUID and path type information.\n\n•   Decode the underlying filesystem file handle to underlying dentry.\n\n•   For a lower file handle, lookup the handle in index directory by name.\n\n•   If a whiteout is found in index, return ESTALE. This represents an overlay object\nthat was deleted after its file handle was encoded.\n\n•   For a non-directory, instantiate a disconnected overlay dentry from the decoded\nunderlying dentry, the path type and index inode, if found.\n\n•   For a directory, use the connected underlying decoded dentry, path type and\nindex, to lookup a connected overlay dentry.\n\nDecoding a non-directory file handle may return a disconnected dentry. copyup of that\ndisconnected dentry will create an upper index entry with no upper alias.\n\nWhen overlay filesystem has multiple lower layers, a middle layer directory may have a\n\"redirect\" to lower directory. Because middle layer \"redirects\" are not indexed, a lower\nfile handle that was encoded from the \"redirect\" origin directory, cannot be used to find\nthe middle or upper layer directory. Similarly, a lower file handle that was encoded from\na descendant of the \"redirect\" origin directory, cannot be used to reconstruct a\nconnected overlay path. To mitigate the cases of directories that cannot be decoded from\na lower file handle, these directories are copied up on encode and encoded as an upper\nfile handle. On an overlay filesystem with no upper layer this mitigation cannot be used\nNFS export in this setup requires turning off redirect follow (e.g.\n\"redirectdir=nofollow\").\n\nThe overlay filesystem does not support non-directory connectable file handles, so\nexporting with the subtreecheck exportfs configuration will cause failures to lookup\nfiles over NFS.\n\nWhen the NFS export feature is enabled, all directory index entries are verified on mount\ntime to check that upper file handles are not stale. This verification may cause\nsignificant overhead in some cases.\n\nNote: the mount options index=off,nfsexport=on are conflicting for a read-write mount\nand will result in an error.\n\nxinfo={on|off|auto}\nThe \"xino\" feature composes a unique object identifier from the real object stino and an\nunderlying fsid index. The \"xino\" feature uses the high inode number bits for fsid,\nbecause the underlying filesystems rarely use the high inode number bits. In case the\nunderlying inode number does overflow into the high xino bits, overlay filesystem will\nfall back to the non xino behavior for that inode.\n\nFor a detailed description of the effect of this option please refer to\nhttps://www.kernel.org/doc/html/latest/filesystems/overlayfs.html?highlight=overlayfs\n\nmetacopy={on|off}\nWhen metadata only copy up feature is enabled, overlayfs will only copy up metadata (as\nopposed to whole file), when a metadata specific operation like chown/chmod is performed.\nFull file will be copied up later when file is opened for WRITE operation.\n\nIn other words, this is delayed data copy up operation and data is copied up when there\nis a need to actually modify data.\n"
                },
                {
                    "name": "volatile",
                    "content": "Volatile mounts are not guaranteed to survive a crash. It is strongly recommended that\nvolatile mounts are only used if data written to the overlay can be recreated without\nsignificant effort.\n\nThe advantage of mounting with the \"volatile\" option is that all forms of sync calls to\nthe upper filesystem are omitted.\n\nIn order to avoid a giving a false sense of safety, the syncfs (and fsync) semantics of\nvolatile mounts are slightly different than that of the rest of VFS. If any writeback\nerror occurs on the upperdir’s filesystem after a volatile mount takes place, all sync\nfunctions will return an error. Once this condition is reached, the filesystem will not\nrecover, and every subsequent sync call will return an error, even if the upperdir has\nnot experience a new error since the last sync call.\n\nWhen overlay is mounted with \"volatile\" option, the directory\n\"$workdir/work/incompat/volatile\" is created. During next mount, overlay checks for this\ndirectory and refuses to mount if present. This is a strong indicator that user should\nthrow away upper and work directories and create fresh one. In very limited cases where\nthe user knows that the system has not crashed and contents of upperdir are intact, The\n\"volatile\" directory can be removed.\n"
                },
                {
                    "name": "Mount options for reiserfs",
                    "content": "Reiserfs is a journaling filesystem.\n"
                },
                {
                    "name": "conv",
                    "content": "Instructs version 3.6 reiserfs software to mount a version 3.5 filesystem, using the 3.6\nformat for newly created objects. This filesystem will no longer be compatible with\nreiserfs 3.5 tools.\n\nhash={rupasov|tea|r5|detect}\nChoose which hash function reiserfs will use to find files within directories.\n\nrupasov\nA hash invented by Yury Yu. Rupasov. It is fast and preserves locality, mapping\nlexicographically close file names to close hash values. This option should not be\nused, as it causes a high probability of hash collisions.\n\ntea\nA Davis-Meyer function implemented by Jeremy Fitzhardinge. It uses hash permuting\nbits in the name. It gets high randomness and, therefore, low probability of hash\ncollisions at some CPU cost. This may be used if EHASHCOLLISION errors are\nexperienced with the r5 hash.\n\nr5\nA modified version of the rupasov hash. It is used by default and is the best choice\nunless the filesystem has huge directories and unusual file-name patterns.\n\ndetect\nInstructs mount to detect which hash function is in use by examining the filesystem\nbeing mounted, and to write this information into the reiserfs superblock. This is\nonly useful on the first mount of an old format filesystem.\n\nhashedrelocation\nTunes the block allocator. This may provide performance improvements in some situations.\n\nnounhashedrelocation\nTunes the block allocator. This may provide performance improvements in some situations.\n"
                },
                {
                    "name": "noborder",
                    "content": "Disable the border allocator algorithm invented by Yury Yu. Rupasov. This may provide\nperformance improvements in some situations.\n"
                },
                {
                    "name": "nolog",
                    "content": "Disable journaling. This will provide slight performance improvements in some situations\nat the cost of losing reiserfs’s fast recovery from crashes. Even with this option turned\non, reiserfs still performs all journaling operations, save for actual writes into its\njournaling area. Implementation of nolog is a work in progress.\n"
                },
                {
                    "name": "notail",
                    "content": "By default, reiserfs stores small files and 'file tails' directly into its tree. This\nconfuses some utilities such as lilo(8). This option is used to disable packing of files\ninto the tree.\n"
                },
                {
                    "name": "replayonly",
                    "content": "Replay the transactions which are in the journal, but do not actually mount the\nfilesystem. Mainly used by reiserfsck.\n\nresize=number\nA remount option which permits online expansion of reiserfs partitions. Instructs\nreiserfs to assume that the device has number blocks. This option is designed for use\nwith devices which are under logical volume management (LVM). There is a special resizer\nutility which can be obtained from ftp://ftp.namesys.com/pub/reiserfsprogs.\n\nuserxattr\nEnable Extended User Attributes. See the attr(1) manual page.\n"
                },
                {
                    "name": "acl",
                    "content": "Enable POSIX Access Control Lists. See the acl(5) manual page.\n\nbarrier=none / barrier=flush\nThis disables / enables the use of write barriers in the journaling code. barrier=none\ndisables, barrier=flush enables (default). This also requires an IO stack which can\nsupport barriers, and if reiserfs gets an error on a barrier write, it will disable\nbarriers again with a warning. Write barriers enforce proper on-disk ordering of journal\ncommits, making volatile disk write caches safe to use, at some performance penalty. If\nyour disks are battery-backed in one way or another, disabling barriers may safely\nimprove performance.\n"
                },
                {
                    "name": "Mount options for ubifs",
                    "content": "UBIFS is a flash filesystem which works on top of UBI volumes. Note that atime is not\nsupported and is always turned off.\n\nThe device name may be specified as\n\nubiXY\nUBI device number X, volume number Y\n\nubiY\nUBI device number 0, volume number Y\n\nubiX:NAME\nUBI device number X, volume with name NAME\n\nubi:NAME\nUBI device number 0, volume with name NAME\n\nAlternative ! separator may be used instead of :.\n\nThe following mount options are available:\n\nbulkread\nEnable bulk-read. VFS read-ahead is disabled because it slows down the filesystem.\nBulk-Read is an internal optimization. Some flashes may read faster if the data are read\nat one go, rather than at several read requests. For example, OneNAND can do\n\"read-while-load\" if it reads more than one NAND page.\n\nnobulkread\nDo not bulk-read. This is the default.\n\nchkdatacrc\nCheck data CRC-32 checksums. This is the default.\n\nnochkdatacrc\nDo not check data CRC-32 checksums. With this option, the filesystem does not check\nCRC-32 checksum for data, but it does check it for the internal indexing information.\nThis option only affects reading, not writing. CRC-32 is always calculated when writing\nthe data.\n\ncompr={none|lzo|zlib}\nSelect the default compressor which is used when new files are written. It is still\npossible to read compressed files if mounted with the none option.\n"
                },
                {
                    "name": "Mount options for udf",
                    "content": "UDF is the \"Universal Disk Format\" filesystem defined by OSTA, the Optical Storage Technology\nAssociation, and is often used for DVD-ROM, frequently in the form of a hybrid UDF/ISO-9660\nfilesystem. It is, however, perfectly usable by itself on disk drives, flash drives and other\nblock devices. See also iso9660.\n"
                },
                {
                    "name": "uid=",
                    "content": "Make all files in the filesystem belong to the given user. uid=forget can be specified\nindependently of (or usually in addition to) uid=<user> and results in UDF not storing\nuids to the media. In fact the recorded uid is the 32-bit overflow uid -1 as defined by\nthe UDF standard. The value is given as either <user> which is a valid user name or the\ncorresponding decimal user id, or the special string \"forget\".\n"
                },
                {
                    "name": "gid=",
                    "content": "Make all files in the filesystem belong to the given group. gid=forget can be specified\nindependently of (or usually in addition to) gid=<group> and results in UDF not storing\ngids to the media. In fact the recorded gid is the 32-bit overflow gid -1 as defined by\nthe UDF standard. The value is given as either <group> which is a valid group name or the\ncorresponding decimal group id, or the special string \"forget\".\n"
                },
                {
                    "name": "umask=",
                    "content": "Mask out the given permissions from all inodes read from the filesystem. The value is\ngiven in octal.\n"
                },
                {
                    "name": "mode=",
                    "content": "If mode= is set the permissions of all non-directory inodes read from the filesystem will\nbe set to the given mode. The value is given in octal.\n"
                },
                {
                    "name": "dmode=",
                    "content": "If dmode= is set the permissions of all directory inodes read from the filesystem will be\nset to the given dmode. The value is given in octal.\n"
                },
                {
                    "name": "bs=",
                    "content": "Set the block size. Default value prior to kernel version 2.6.30 was 2048. Since 2.6.30\nand prior to 4.11 it was logical device block size with fallback to 2048. Since 4.11 it\nis logical block size with fallback to any valid block size between logical device block\nsize and 4096.\n\nFor other details see the mkudffs(8) 2.0+ manpage, sections COMPATIBILITY and BLOCK SIZE.\n"
                },
                {
                    "name": "unhide",
                    "content": "Show otherwise hidden files.\n"
                },
                {
                    "name": "undelete",
                    "content": "Show deleted files in lists.\n"
                },
                {
                    "name": "adinicb",
                    "content": "Embed data in the inode. (default)\n"
                },
                {
                    "name": "noadinicb",
                    "content": "Don’t embed data in the inode.\n"
                },
                {
                    "name": "shortad",
                    "content": "Use short UDF address descriptors.\n"
                },
                {
                    "name": "longad",
                    "content": "Use long UDF address descriptors. (default)\n"
                },
                {
                    "name": "nostrict",
                    "content": "Unset strict conformance.\n"
                },
                {
                    "name": "iocharset=",
                    "content": "Set the NLS character set. This requires kernel compiled with CONFIGUDFNLS option.\n"
                },
                {
                    "name": "utf8",
                    "content": "Set the UTF-8 character set.\n"
                },
                {
                    "name": "Mount options for debugging and disaster recovery",
                    "content": ""
                },
                {
                    "name": "novrs",
                    "content": "Ignore the Volume Recognition Sequence and attempt to mount anyway.\n"
                },
                {
                    "name": "session=",
                    "content": "Select the session number for multi-session recorded optical media. (default= last\nsession)\n"
                },
                {
                    "name": "anchor=",
                    "content": "Override standard anchor location. (default= 256)\n"
                },
                {
                    "name": "lastblock=",
                    "content": "Set the last block of the filesystem.\n"
                },
                {
                    "name": "Unused historical mount options that may be encountered and should be removed",
                    "content": ""
                },
                {
                    "name": "uid=ignore",
                    "content": "Ignored, use uid=<user> instead.\n"
                },
                {
                    "name": "gid=ignore",
                    "content": "Ignored, use gid=<group> instead.\n"
                },
                {
                    "name": "volume=",
                    "content": "Unimplemented and ignored.\n"
                },
                {
                    "name": "partition=",
                    "content": "Unimplemented and ignored.\n"
                },
                {
                    "name": "fileset=",
                    "content": "Unimplemented and ignored.\n"
                },
                {
                    "name": "rootdir=",
                    "content": "Unimplemented and ignored.\n"
                },
                {
                    "name": "Mount options for ufs",
                    "content": "ufstype=value\nUFS is a filesystem widely used in different operating systems. The problem are\ndifferences among implementations. Features of some implementations are undocumented, so\nits hard to recognize the type of ufs automatically. That’s why the user must specify the\ntype of ufs by mount option. Possible values are:\n\nold\nOld format of ufs, this is the default, read only. (Don’t forget to give the -r\noption.)\n\n44bsd\nFor filesystems created by a BSD-like system (NetBSD, FreeBSD, OpenBSD).\n\nufs2\nUsed in FreeBSD 5.x supported as read-write.\n\n5xbsd\nSynonym for ufs2.\n\nsun\nFor filesystems created by SunOS or Solaris on Sparc.\n\nsunx86\nFor filesystems created by Solaris on x86.\n\nhp\nFor filesystems created by HP-UX, read-only.\n\nnextstep\nFor filesystems created by NeXTStep (on NeXT station) (currently read only).\n\nnextstep-cd\nFor NextStep CDROMs (blocksize == 2048), read-only.\n\nopenstep\nFor filesystems created by OpenStep (currently read only). The same filesystem type\nis also used by Mac OS X.\n\nonerror=value\nSet behavior on error:\n\npanic\nIf an error is encountered, cause a kernel panic.\n\n[lock|umount|repair]\nThese mount options don’t do anything at present; when an error is encountered only a\nconsole message is printed.\n"
                },
                {
                    "name": "Mount options for umsdos",
                    "content": "See mount options for msdos. The dotsOK option is explicitly killed by umsdos.\n"
                },
                {
                    "name": "Mount options for vfat",
                    "content": "First of all, the mount options for fat are recognized. The dotsOK option is explicitly\nkilled by vfat. Furthermore, there are\n\nunixlate\nTranslate unhandled Unicode characters to special escaped sequences. This lets you backup\nand restore filenames that are created with any Unicode characters. Without this option,\na '?' is used when no translation is possible. The escape character is ':' because it is\notherwise invalid on the vfat filesystem. The escape sequence that gets used, where u is\nthe Unicode character, is: ':', (u & 0x3f), ((u>>6) & 0x3f), (u>>12).\n"
                },
                {
                    "name": "posix",
                    "content": "Allow two files with names that only differ in case. This option is obsolete.\n"
                },
                {
                    "name": "nonumtail",
                    "content": "First try to make a short name without sequence number, before trying name~num.ext.\n"
                },
                {
                    "name": "utf8",
                    "content": "UTF8 is the filesystem safe 8-bit encoding of Unicode that is used by the console. It can\nbe enabled for the filesystem with this option or disabled with utf8=0, utf8=no or\nutf8=false. If unixlate gets set, UTF8 gets disabled.\n\nshortname=mode\nDefines the behavior for creation and display of filenames which fit into 8.3 characters.\nIf a long name for a file exists, it will always be the preferred one for display. There\nare four modes:\n\nlower\nForce the short name to lower case upon display; store a long name when the short\nname is not all upper case.\n\nwin95\nForce the short name to upper case upon display; store a long name when the short\nname is not all upper case.\n\nwinnt\nDisplay the short name as is; store a long name when the short name is not all lower\ncase or all upper case.\n\nmixed\nDisplay the short name as is; store a long name when the short name is not all upper\ncase. This mode is the default since Linux 2.6.32.\n"
                },
                {
                    "name": "Mount options for usbfs",
                    "content": "devuid=uid and devgid=gid and devmode=mode\nSet the owner and group and mode of the device files in the usbfs filesystem (default:\nuid=gid=0, mode=0644). The mode is given in octal.\n\nbusuid=uid and busgid=gid and busmode=mode\nSet the owner and group and mode of the bus directories in the usbfs filesystem (default:\nuid=gid=0, mode=0555). The mode is given in octal.\n\nlistuid=uid and listgid=gid and listmode=mode\nSet the owner and group and mode of the file devices (default: uid=gid=0, mode=0444). The\nmode is given in octal.\n"
                },
                {
                    "name": "DM-VERITY SUPPORT (EXPERIMENTAL)",
                    "content": "The device-mapper verity target provides read-only transparent integrity checking of block\ndevices using kernel crypto API. The mount command can open the dm-verity device and do the\nintegrity verification before on the device filesystem is mounted. Requires libcryptsetup\nwith in libmount (optionally via dlopen(3)). If libcryptsetup supports extracting the root\nhash of an already mounted device, existing devices will be automatically reused in case of a\nmatch. Mount options for dm-verity:\n\nverity.hashdevice=path\nPath to the hash tree device associated with the source volume to pass to dm-verity.\n\nverity.roothash=hex\nHex-encoded hash of the root of verity.hashdevice. Mutually exclusive with\nverity.roothashfile.\n\nverity.roothashfile=path\nPath to file containing the hex-encoded hash of the root of verity.hashdevice. Mutually\nexclusive with verity.roothash.\n\nverity.hashoffset=offset\nIf the hash tree device is embedded in the source volume, offset (default: 0) is used by\ndm-verity to get to the tree.\n\nverity.fecdevice=path\nPath to the Forward Error Correction (FEC) device associated with the source volume to\npass to dm-verity. Optional. Requires kernel built with CONFIGDMVERITYFEC.\n\nverity.fecoffset=offset\nIf the FEC device is embedded in the source volume, offset (default: 0) is used by\ndm-verity to get to the FEC area. Optional.\n\nverity.fecroots=value\nParity bytes for FEC (default: 2). Optional.\n\nverity.roothashsig=path\nPath to pkcs7(1ssl) signature of root hash hex string. Requires\ncryptactivatebysignedkey() from cryptsetup and kernel built with\nCONFIGDMVERITYVERIFYROOTHASHSIG. For device reuse, signatures have to be either used\nby all mounts of a device or by none. Optional.\n\nSupported since util-linux v2.35.\n\nFor example commands:\n\nmksquashfs /etc /tmp/etc.squashfs\ndd if=/dev/zero of=/tmp/etc.hash bs=1M count=10\nveritysetup format /tmp/etc.squashfs /tmp/etc.hash\nopenssl smime -sign -in <hash> -nocerts -inkey private.key \\\n-signer private.crt -noattr -binary -outform der -out /tmp/etc.roothash.p7s\nmount -o verity.hashdevice=/tmp/etc.hash,verity.roothash=<hash>,\\\nverity.roothashsig=/tmp/etc.roothash.p7s /tmp/etc.squashfs /mnt\n\ncreate squashfs image from /etc directory, verity hash device and mount verified filesystem\nimage to /mnt. The kernel will verify that the root hash is signed by a key from the kernel\nkeyring if roothashsig is used.\n"
                }
            ]
        },
        "LOOP-DEVICE SUPPORT": {
            "content": "One further possible type is a mount via the loop device. For example, the command\n\nmount /tmp/disk.img /mnt -t vfat -o loop=/dev/loop3\n\nwill set up the loop device /dev/loop3 to correspond to the file /tmp/disk.img, and then\nmount this device on /mnt.\n\nIf no explicit loop device is mentioned (but just an option '-o loop' is given), then mount\nwill try to find some unused loop device and use that, for example\n\nmount /tmp/disk.img /mnt -o loop\n\nThe mount command automatically creates a loop device from a regular file if a filesystem\ntype is not specified or the filesystem is known for libblkid, for example:\n\nmount /tmp/disk.img /mnt\n\nmount -t ext4 /tmp/disk.img /mnt\n\nThis type of mount knows about three options, namely loop, offset and sizelimit, that are\nreally options to losetup(8). (These options can be used in addition to those specific to the\nfilesystem type.)\n\nSince Linux 2.6.25 auto-destruction of loop devices is supported, meaning that any loop\ndevice allocated by mount will be freed by umount independently of /etc/mtab.\n\nYou can also free a loop device by hand, using losetup -d or umount -d.\n\nSince util-linux v2.29, mount re-uses the loop device rather than initializing a new device\nif the same backing file is already used for some loop device with the same offset and\nsizelimit. This is necessary to avoid a filesystem corruption.\n",
            "subsections": []
        },
        "EXIT STATUS": {
            "content": "mount has the following exit status values (the bits can be ORed):\n\n0\nsuccess\n\n1\nincorrect invocation or permissions\n\n2\nsystem error (out of memory, cannot fork, no more loop devices)\n\n4\ninternal mount bug\n\n8\nuser interrupt\n\n16\nproblems writing or locking /etc/mtab\n\n32\nmount failure\n\n64\nsome mount succeeded\n\nThe command mount -a returns 0 (all succeeded), 32 (all failed), or 64 (some failed, some\nsucceeded).\n",
            "subsections": []
        },
        "EXTERNAL HELPERS": {
            "content": "The syntax of external mount helpers is:\n\n/sbin/mount.suffix spec dir [-sfnv] [-N namespace] [-o options] [-t type.subtype]\n\nwhere the suffix is the filesystem type and the -sfnvoN options have the same meaning as the\nnormal mount options. The -t option is used for filesystems with subtypes support (for\nexample /sbin/mount.fuse -t fuse.sshfs).\n\nThe command mount does not pass the mount options unbindable, runbindable, private, rprivate,\nslave, rslave, shared, rshared, auto, noauto, comment, x-*, loop, offset and sizelimit to the\nmount.<suffix> helpers. All other options are used in a comma-separated list as an argument\nto the -o option.\n",
            "subsections": []
        },
        "ENVIRONMENT": {
            "content": "LIBMOUNTFSTAB=<path>\noverrides the default location of the fstab file (ignored for suid)\n\nLIBMOUNTMTAB=<path>\noverrides the default location of the mtab file (ignored for suid)\n\nLIBMOUNTDEBUG=all\nenables libmount debug output\n\nLIBBLKIDDEBUG=all\nenables libblkid debug output\n\nLOOPDEVDEBUG=all\nenables loop device setup debug output\n",
            "subsections": []
        },
        "FILES": {
            "content": "See also \"The files /etc/fstab, /etc/mtab and /proc/mounts\" section above.\n\n/etc/fstab\nfilesystem table\n\n/run/mount\nlibmount private runtime directory\n\n/etc/mtab\ntable of mounted filesystems or symlink to /proc/mounts\n\n/etc/mtab~\nlock file (unused on systems with mtab symlink)\n\n/etc/mtab.tmp\ntemporary file (unused on systems with mtab symlink)\n\n/etc/filesystems\na list of filesystem types to try\n",
            "subsections": []
        },
        "HISTORY": {
            "content": "A mount command existed in Version 5 AT&T UNIX.\n",
            "subsections": []
        },
        "BUGS": {
            "content": "It is possible for a corrupted filesystem to cause a crash.\n\nSome Linux filesystems don’t support -o sync and -o dirsync (the ext2, ext3, ext4, fat and\nvfat filesystems do support synchronous updates (a la BSD) when mounted with the sync\noption).\n\nThe -o remount may not be able to change mount parameters (all ext2fs-specific parameters,\nexcept sb, are changeable with a remount, for example, but you can’t change gid or umask for\nthe fatfs).\n\nIt is possible that the files /etc/mtab and /proc/mounts don’t match on systems with a\nregular mtab file. The first file is based only on the mount command options, but the content\nof the second file also depends on the kernel and others settings (e.g. on a remote NFS\nserver — in certain cases the mount command may report unreliable information about an NFS\nmount point and the /proc/mount file usually contains more reliable information.) This is\nanother reason to replace the mtab file with a symlink to the /proc/mounts file.\n\nChecking files on NFS filesystems referenced by file descriptors (i.e. the fcntl and ioctl\nfamilies of functions) may lead to inconsistent results due to the lack of a consistency\ncheck in the kernel even if the noac mount option is used.\n\nThe loop option with the offset or sizelimit options used may fail when using older kernels\nif the mount command can’t confirm that the size of the block device has been configured as\nrequested. This situation can be worked around by using the losetup(8) command manually\nbefore calling mount with the configured loop device.\n",
            "subsections": []
        },
        "AUTHORS": {
            "content": "Karel Zak <kzak@redhat.com>\n",
            "subsections": []
        },
        "SEE ALSO": {
            "content": "mount(2), umount(2), filesystems(5), fstab(5), nfs(5), xfs(5), mountnamespaces(7), xattr(7),\ne2label(8), findmnt(8), losetup(8), lsblk(8), mke2fs(8), mountd(8), nfsd(8), swapon(8),\ntune2fs(8), umount(8), xfsadmin(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": "The mount command is part of the util-linux package which can be downloaded from Linux Kernel\nArchive <https://www.kernel.org/pub/linux/utils/util-linux/>.\n\n\n\nutil-linux 2.37.2                            2021-08-16                                     MOUNT(8)",
            "subsections": []
        }
    },
    "summary": "mount - mount a filesystem",
    "flags": [],
    "examples": [],
    "see_also": [
        {
            "name": "umount",
            "section": "2",
            "url": "https://www.chedong.com/phpMan.php/man/umount/2/json"
        },
        {
            "name": "filesystems",
            "section": "5",
            "url": "https://www.chedong.com/phpMan.php/man/filesystems/5/json"
        },
        {
            "name": "fstab",
            "section": "5",
            "url": "https://www.chedong.com/phpMan.php/man/fstab/5/json"
        },
        {
            "name": "nfs",
            "section": "5",
            "url": "https://www.chedong.com/phpMan.php/man/nfs/5/json"
        },
        {
            "name": "xfs",
            "section": "5",
            "url": "https://www.chedong.com/phpMan.php/man/xfs/5/json"
        },
        {
            "name": "mountnamespaces",
            "section": "7",
            "url": "https://www.chedong.com/phpMan.php/man/mountnamespaces/7/json"
        },
        {
            "name": "xattr",
            "section": "7",
            "url": "https://www.chedong.com/phpMan.php/man/xattr/7/json"
        },
        {
            "name": "e2label",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/e2label/8/json"
        },
        {
            "name": "findmnt",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/findmnt/8/json"
        },
        {
            "name": "losetup",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/losetup/8/json"
        },
        {
            "name": "lsblk",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/lsblk/8/json"
        },
        {
            "name": "mke2fs",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/mke2fs/8/json"
        },
        {
            "name": "mountd",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/mountd/8/json"
        },
        {
            "name": "nfsd",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/nfsd/8/json"
        },
        {
            "name": "swapon",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/swapon/8/json"
        },
        {
            "name": "tune2fs",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/tune2fs/8/json"
        },
        {
            "name": "umount",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/umount/8/json"
        },
        {
            "name": "xfsadmin",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/xfsadmin/8/json"
        }
    ]
}