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   mount    ( 8 )

смонтировать файловую систему (mount a filesystem)

Параметры командной строки (Command line options)

The full set of mount options used by an invocation of mount is determined by first extracting the mount options for the filesystem from the fstab table, then applying any options specified by the -o argument, and finally applying a -r or -w option, when present.

The mount command does not pass all command-line options to the /sbin/mount.suffix mount helpers. The interface between mount and the mount helpers is described below in the section EXTERNAL HELPERS.

Command-line options available for the mount command are:

-a, --all Mount all filesystems (of the given types) mentioned in fstab (except for those whose line contains the noauto keyword). The filesystems are mounted following their order in fstab. The mount command compares filesystem source, target (and fs root for bind mount or btrfs) to detect already mounted filesystems. The kernel table with already mounted filesystems is cached during mount --all. This means that all duplicated fstab entries will be mounted.

The option --all is possible to use for remount operation too. In this case all filters (-t and -O) are applied to the table of already mounted filesystems.

Since version 2.35 is possible to use the command line option -o to alter mount options from fstab (see also --options-mode).

Note that it is a bad practice to use mount -a for fstab checking. The recommended solution is findmnt --verify.

-B, --bind Remount a subtree somewhere else (so that its contents are available in both places). See above, under Bind mounts.

-c, --no-canonicalize Don't canonicalize paths. The mount command canonicalizes all paths (from the command line or fstab) by default. This option can be used together with the -f flag for already canonicalized absolute paths. The option is designed for mount helpers which call mount -i. It is strongly recommended to not use this command-line option for normal mount operations.

Note that mount does not pass this option to the /sbin/mount.type helpers.

-F, --fork (Used in conjunction with -a.) Fork off a new incarnation of mount for each device. This will do the mounts on different devices or different NFS servers in parallel. This has the advantage that it is faster; also NFS timeouts proceed in parallel. A disadvantage is that the order of the mount operations is undefined. Thus, you cannot use this option if you want to mount both /usr and /usr/spool.

-f, --fake Causes everything to be done except for the actual system call; if it's not obvious, this "fakes" mounting the filesystem. This option is useful in conjunction with the -v flag to determine what the mount command is trying to do. It can also be used to add entries for devices that were mounted earlier with the -n option. The -f option checks for an existing record in /etc/mtab and fails when the record already exists (with a regular non-fake mount, this check is done by the kernel).

-i, --internal-only Don't call the /sbin/mount.filesystem helper even if it exists.

-L, --label label Mount the partition that has the specified label.

-l, --show-labels Add the labels in the mount output. mount must have permission to read the disk device (e.g. be set-user-ID root) for this to work. One can set such a label for ext2, ext3 or ext4 using the e2label(8) utility, or for XFS using xfs_admin(8), or for reiserfs using reiserfstune(8).

-M, --move Move a subtree to some other place. See above, the subsection The move operation.

-m, --mkdir[=mode] Allow to make a target directory (mountpoint) if it does not exist yet. Alias to "-o X-mount.mkdir[=mode]", the default mode is 0755. For more details see X-mount.mkdir below.

-n, --no-mtab Mount without writing in /etc/mtab. This is necessary for example when /etc is on a read-only filesystem.

-N, --namespace ns Perform the mount operation in the mount namespace specified by ns. ns is either PID of process running in that namespace or special file representing that namespace.

mount switches to the mount namespace when it reads /etc/fstab, writes /etc/mtab: (or writes to _/run/mount) and calls the mount(2) system call, otherwise it runs in the original mount namespace. This means that the target namespace does not have to contain any libraries or other requirements necessary to execute the mount(2) call.

See mount_namespaces(7) for more information.

-O, --test-opts opts Limit the set of filesystems to which the -a option applies. In this regard it is like the -t option except that -O is useless without -a. For example, the command

mount -a -O no_netdev

mounts all filesystems except those which have the option netdev specified in the options field in the /etc/fstab file.

It is different from -t in that each option is matched exactly; a leading no at the beginning of one option does not negate the rest.

The -t and -O options are cumulative in effect; that is, the command

mount -a -t ext2 -O _netdev

mounts all ext2 filesystems with the _netdev option, not all filesystems that are either ext2 or have the _netdev option specified.

-o, --options opts Use the specified mount options. The opts argument is a comma-separated list. For example:

mount LABEL=mydisk -o noatime,nodev,nosuid

For more details, see the FILESYSTEM-INDEPENDENT MOUNT OPTIONS and FILESYSTEM-SPECIFIC MOUNT OPTIONS sections.

--options-mode mode Controls how to combine options from fstab/mtab with options from the command line. mode can be one of ignore, append, prepend or replace. For example, append means that options from fstab are appended to options from the command line. The default value is prepend — it means command line options are evaluated after fstab options. Note that the last option wins if there are conflicting ones.

--options-source source Source of default options. source is a comma-separated list of fstab, mtab and disable. disable disables fstab and mtab and disables --options-source-force. The default value is fstab,mtab.

--options-source-force Use options from fstab/mtab even if both device and dir are specified.

-R, --rbind Remount a subtree and all possible submounts somewhere else (so that its contents are available in both places). See above, the subsection Bind mounts.

-r, --read-only Mount the filesystem read-only. A synonym is -o ro.

Note that, depending on the filesystem type, state and kernel behavior, the system may still write to the device. For example, ext3 and ext4 will replay the journal if the filesystem is dirty. To prevent this kind of write access, you may want to mount an ext3 or ext4 filesystem with the ro,noload mount options or set the block device itself to read-only mode, see the blockdev(8) command.

-s Tolerate sloppy mount options rather than failing. This will ignore mount options not supported by a filesystem type. Not all filesystems support this option. Currently it's supported by the mount.nfs mount helper only.

--source device If only one argument for the mount command is given, then the argument might be interpreted as the target (mountpoint) or source (device). This option allows you to explicitly define that the argument is the mount source.

--target directory If only one argument for the mount command is given, then the argument might be interpreted as the target (mountpoint) or source (device). This option allows you to explicitly define that the argument is the mount target.

--target-prefix directory Prepend the specified directory to all mount targets. This option can be used to follow fstab, but mount operations are done in another place, for example:

mount --all --target-prefix /chroot -o X-mount.mkdir

mounts all from system fstab to /chroot, all missing mountpoint are created (due to X-mount.mkdir). See also --fstab to use an alternative fstab.

-T, --fstab path Specifies an alternative fstab file. If path is a directory, then the files in the directory are sorted by strverscmp(3); files that start with "." or without an .fstab extension are ignored. The option can be specified more than once. This option is mostly designed for initramfs or chroot scripts where additional configuration is specified beyond standard system configuration.

Note that mount does not pass the option --fstab to the /sbin/mount.type helpers, meaning that the alternative fstab files will be invisible for the helpers. This is no problem for normal mounts, but user (non-root) mounts always require fstab to verify the user's rights.

-t, --types fstype The argument following the -t is used to indicate the filesystem type. The filesystem types which are currently supported depend on the running kernel. See /proc/filesystems and /lib/modules/$(uname -r)/kernel/fs for a complete list of the filesystems. The most common are ext2, ext3, ext4, xfs, btrfs, vfat, sysfs, proc, nfs and cifs.

The programs mount and umount(8) support filesystem subtypes. The subtype is defined by a '.subtype' suffix. For example 'fuse.sshfs'. It's recommended to use subtype notation rather than add any prefix to the mount source (for example 'sshfs#example.com' is deprecated).

If no -t option is given, or if the auto type is specified, mount will try to guess the desired type. mount uses the libblkid(3) library for guessing the filesystem type; if that does not turn up anything that looks familiar, mount will try to read the file /etc/filesystems, or, if that does not exist, /proc/filesystems. All of the filesystem types listed there will be tried, except for those that are labeled "nodev" (e.g. devpts, proc and nfs). If /etc/filesystems ends in a line with a single *, mount will read /proc/filesystems afterwards. While trying, all filesystem types will be mounted with the mount option silent.

The auto type may be useful for user-mounted floppies. Creating a file /etc/filesystems can be useful to change the probe order (e.g., to try vfat before msdos or ext3 before ext2) or if you use a kernel module autoloader.

More than one type may be specified in a comma-separated list, for the -t option as well as in an /etc/fstab entry. The list of filesystem types for the -t option can be prefixed with no to specify the filesystem types on which no action should be taken. The prefix no has no effect when specified in an /etc/fstab entry.

The prefix no can be meaningful with the -a option. For example, the command

mount -a -t nomsdos,smbfs

mounts all filesystems except those of type msdos and smbfs.

For most types all the mount program has to do is issue a simple mount(2) system call, and no detailed knowledge of the filesystem type is required. For a few types however (like nfs, nfs4, cifs, smbfs, ncpfs) an ad hoc code is necessary. The nfs, nfs4, cifs, smbfs, and ncpfs filesystems have a separate mount program. In order to make it possible to treat all types in a uniform way, mount will execute the program /sbin/mount.type (if that exists) when called with type type. Since different versions of the smbmount program have different calling conventions, /sbin/mount.smbfs may have to be a shell script that sets up the desired call.

-U, --uuid uuid Mount the partition that has the specified uuid.

-v, --verbose Verbose mode.

-w, --rw, --read-write Mount the filesystem read/write. Read-write is the kernel default and the mount default is to try read-only if the previous mount(2) syscall with read-write flags on write-protected devices failed.

A synonym is -o rw.

Note that specifying -w on the command line forces mount to never try read-only mount on write-protected devices or already mounted read-only filesystems.

-V, --version Display version information and exit.

-h, --help Display help text and exit.