rclone/cmd/mountlib/mount.md
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rclone @ allows Linux, FreeBSD, macOS and Windows to mount any of Rclone's cloud storage systems as a file system with FUSE.

First set up your remote using rclone config. Check it works with rclone ls etc.

On Linux and macOS, you can run mount in either foreground or background (aka daemon) mode. Mount runs in foreground mode by default. Use the --daemon flag to force background mode. On Windows you can run mount in foreground only, the flag is ignored.

In background mode rclone acts as a generic Unix mount program: the main program starts, spawns background rclone process to setup and maintain the mount, waits until success or timeout and exits with appropriate code (killing the child process if it fails).

On Linux/macOS/FreeBSD start the mount like this, where /path/to/local/mount is an empty existing directory:

rclone @ remote:path/to/files /path/to/local/mount

On Windows you can start a mount in different ways. See below for details. If foreground mount is used interactively from a console window, rclone will serve the mount and occupy the console so another window should be used to work with the mount until rclone is interrupted e.g. by pressing Ctrl-C.

The following examples will mount to an automatically assigned drive, to specific drive letter X:, to path C:\path\parent\mount (where parent directory or drive must exist, and mount must not exist, and is not supported when mounting as a network drive), and the last example will mount as network share \\cloud\remote and map it to an automatically assigned drive:

rclone @ remote:path/to/files *
rclone @ remote:path/to/files X:
rclone @ remote:path/to/files C:\path\parent\mount
rclone @ remote:path/to/files \\cloud\remote

When the program ends while in foreground mode, either via Ctrl+C or receiving a SIGINT or SIGTERM signal, the mount should be automatically stopped.

When running in background mode the user will have to stop the mount manually:

# Linux
fusermount -u /path/to/local/mount
# OS X
umount /path/to/local/mount

The umount operation can fail, for example when the mountpoint is busy. When that happens, it is the user's responsibility to stop the mount manually.

The size of the mounted file system will be set according to information retrieved from the remote, the same as returned by the rclone about command. Remotes with unlimited storage may report the used size only, then an additional 1 PiB of free space is assumed. If the remote does not support the about feature at all, then 1 PiB is set as both the total and the free size.

Installing on Windows

To run rclone @ on Windows, you will need to download and install WinFsp.

WinFsp is an open-source Windows File System Proxy which makes it easy to write user space file systems for Windows. It provides a FUSE emulation layer which rclone uses combination with cgofuse. Both of these packages are by Bill Zissimopoulos who was very helpful during the implementation of rclone @ for Windows.

Mounting modes on windows

Unlike other operating systems, Microsoft Windows provides a different filesystem type for network and fixed drives. It optimises access on the assumption fixed disk drives are fast and reliable, while network drives have relatively high latency and less reliability. Some settings can also be differentiated between the two types, for example that Windows Explorer should just display icons and not create preview thumbnails for image and video files on network drives.

In most cases, rclone will mount the remote as a normal, fixed disk drive by default. However, you can also choose to mount it as a remote network drive, often described as a network share. If you mount an rclone remote using the default, fixed drive mode and experience unexpected program errors, freezes or other issues, consider mounting as a network drive instead.

When mounting as a fixed disk drive you can either mount to an unused drive letter, or to a path representing a nonexistent subdirectory of an existing parent directory or drive. Using the special value * will tell rclone to automatically assign the next available drive letter, starting with Z: and moving backward. Examples:

rclone @ remote:path/to/files *
rclone @ remote:path/to/files X:
rclone @ remote:path/to/files C:\path\parent\mount
rclone @ remote:path/to/files X:

Option --volname can be used to set a custom volume name for the mounted file system. The default is to use the remote name and path.

To mount as network drive, you can add option --network-mode to your @ command. Mounting to a directory path is not supported in this mode, it is a limitation Windows imposes on junctions, so the remote must always be mounted to a drive letter.

rclone @ remote:path/to/files X: --network-mode

A volume name specified with --volname will be used to create the network share path. A complete UNC path, such as \\cloud\remote, optionally with path \\cloud\remote\madeup\path, will be used as is. Any other string will be used as the share part, after a default prefix \\server\. If no volume name is specified then \\server\share will be used. You must make sure the volume name is unique when you are mounting more than one drive, or else the mount command will fail. The share name will treated as the volume label for the mapped drive, shown in Windows Explorer etc, while the complete \\server\share will be reported as the remote UNC path by net use etc, just like a normal network drive mapping.

If you specify a full network share UNC path with --volname, this will implicitly set the --network-mode option, so the following two examples have same result:

rclone @ remote:path/to/files X: --network-mode
rclone @ remote:path/to/files X: --volname \\server\share

You may also specify the network share UNC path as the mountpoint itself. Then rclone will automatically assign a drive letter, same as with * and use that as mountpoint, and instead use the UNC path specified as the volume name, as if it were specified with the --volname option. This will also implicitly set the --network-mode option. This means the following two examples have same result:

rclone @ remote:path/to/files \\cloud\remote
rclone @ remote:path/to/files * --volname \\cloud\remote

There is yet another way to enable network mode, and to set the share path, and that is to pass the "native" libfuse/WinFsp option directly: --fuse-flag --VolumePrefix=\server\share. Note that the path must be with just a single backslash prefix in this case.

Note: In previous versions of rclone this was the only supported method.

Read more about drive mapping

See also Limitations section below.

Windows filesystem permissions

The FUSE emulation layer on Windows must convert between the POSIX-based permission model used in FUSE, and the permission model used in Windows, based on access-control lists (ACL).

The mounted filesystem will normally get three entries in its access-control list (ACL), representing permissions for the POSIX permission scopes: Owner, group and others. By default, the owner and group will be taken from the current user, and the built-in group "Everyone" will be used to represent others. The user/group can be customized with FUSE options "UserName" and "GroupName", e.g. -o UserName=user123 -o GroupName="Authenticated Users". The permissions on each entry will be set according to options --dir-perms and --file-perms, which takes a value in traditional Unix numeric notation.

The default permissions corresponds to --file-perms 0666 --dir-perms 0777, i.e. read and write permissions to everyone. This means you will not be able to start any programs from the mount. To be able to do that you must add execute permissions, e.g. --file-perms 0777 --dir-perms 0777 to add it to everyone. If the program needs to write files, chances are you will have to enable VFS File Caching as well (see also limitations). Note that the default write permission have some restrictions for accounts other than the owner, specifically it lacks the "write extended attributes", as explained next.

The mapping of permissions is not always trivial, and the result you see in Windows Explorer may not be exactly like you expected. For example, when setting a value that includes write access for the group or others scope, this will be mapped to individual permissions "write attributes", "write data" and "append data", but not "write extended attributes". Windows will then show this as basic permission "Special" instead of "Write", because "Write" also covers the "write extended attributes" permission. When setting digit 0 for group or others, to indicate no permissions, they will still get individual permissions "read attributes", "read extended attributes" and "read permissions". This is done for compatibility reasons, e.g. to allow users without additional permissions to be able to read basic metadata about files like in Unix.

WinFsp 2021 (version 1.9) introduced a new FUSE option "FileSecurity", that allows the complete specification of file security descriptors using SDDL. With this you get detailed control of the resulting permissions, compared to use of the POSIX permissions described above, and no additional permissions will be added automatically for compatibility with Unix. Some example use cases will following.

If you set POSIX permissions for only allowing access to the owner, using --file-perms 0600 --dir-perms 0700, the user group and the built-in "Everyone" group will still be given some special permissions, as described above. Some programs may then (incorrectly) interpret this as the file being accessible by everyone, for example an SSH client may warn about "unprotected private key file". You can work around this by specifying -o FileSecurity="D:P(A;;FA;;;OW)", which sets file all access (FA) to the owner (OW), and nothing else.

When setting write permissions then, except for the owner, this does not include the "write extended attributes" permission, as mentioned above. This may prevent applications from writing to files, giving permission denied error instead. To set working write permissions for the built-in "Everyone" group, similar to what it gets by default but with the addition of the "write extended attributes", you can specify -o FileSecurity="D:P(A;;FRFW;;;WD)", which sets file read (FR) and file write (FW) to everyone (WD). If file execute (FX) is also needed, then change to -o FileSecurity="D:P(A;;FRFWFX;;;WD)", or set file all access (FA) to get full access permissions, including delete, with -o FileSecurity="D:P(A;;FA;;;WD)".

Windows caveats

Drives created as Administrator are not visible to other accounts, not even an account that was elevated to Administrator with the User Account Control (UAC) feature. A result of this is that if you mount to a drive letter from a Command Prompt run as Administrator, and then try to access the same drive from Windows Explorer (which does not run as Administrator), you will not be able to see the mounted drive.

If you don't need to access the drive from applications running with administrative privileges, the easiest way around this is to always create the mount from a non-elevated command prompt.

To make mapped drives available to the user account that created them regardless if elevated or not, there is a special Windows setting called linked connections that can be enabled.

It is also possible to make a drive mount available to everyone on the system, by running the process creating it as the built-in SYSTEM account. There are several ways to do this: One is to use the command-line utility PsExec, from Microsoft's Sysinternals suite, which has option -s to start processes as the SYSTEM account. Another alternative is to run the mount command from a Windows Scheduled Task, or a Windows Service, configured to run as the SYSTEM account. A third alternative is to use the WinFsp.Launcher infrastructure). Read more in the install documentation. Note that when running rclone as another user, it will not use the configuration file from your profile unless you tell it to with the --config option. Note also that it is now the SYSTEM account that will have the owner permissions, and other accounts will have permissions according to the group or others scopes. As mentioned above, these will then not get the "write extended attributes" permission, and this may prevent writing to files. You can work around this with the FileSecurity option, see example above.

Note that mapping to a directory path, instead of a drive letter, does not suffer from the same limitations.

Mounting on macOS

Mounting on macOS can be done either via built-in NFS server, macFUSE (also known as osxfuse) or FUSE-T. macFUSE is a traditional FUSE driver utilizing a macOS kernel extension (kext). FUSE-T is an alternative FUSE system which "mounts" via an NFSv4 local server.

NFS mount

This method spins up an NFS server using serve nfs command and mounts it to the specified mountpoint. If you run this in background mode using |--daemon|, you will need to send SIGTERM signal to the rclone process using |kill| command to stop the mount.

macFUSE Notes

If installing macFUSE using dmg packages from the website, rclone will locate the macFUSE libraries without any further intervention. If however, macFUSE is installed using the macports package manager, the following addition steps are required.

sudo mkdir /usr/local/lib
cd /usr/local/lib
sudo ln -s /opt/local/lib/libfuse.2.dylib

FUSE-T Limitations, Caveats, and Notes

There are some limitations, caveats, and notes about how it works. These are current as of FUSE-T version 1.0.14.

ModTime update on read

As per the FUSE-T wiki:

File access and modification times cannot be set separately as it seems to be an issue with the NFS client which always modifies both. Can be reproduced with 'touch -m' and 'touch -a' commands

This means that viewing files with various tools, notably macOS Finder, will cause rlcone to update the modification time of the file. This may make rclone upload a full new copy of the file.

Unicode Normalization

Rclone includes flags for unicode normalization with macFUSE that should be updated for FUSE-T. See this forum post and FUSE-T issue #16. The following flag should be added to the rclone mount command.

-o modules=iconv,from_code=UTF-8,to_code=UTF-8
Read Only mounts

When mounting with --read-only, attempts to write to files will fail silently as opposed to with a clear warning as in macFUSE.

Limitations

Without the use of --vfs-cache-mode this can only write files sequentially, it can only seek when reading. This means that many applications won't work with their files on an rclone mount without --vfs-cache-mode writes or --vfs-cache-mode full. See the VFS File Caching section for more info. When using NFS mount on macOS, if you don't specify |--vfs-cache-mode| the mount point will be read-only.

The bucket-based remotes (e.g. Swift, S3, Google Compute Storage, B2) do not support the concept of empty directories, so empty directories will have a tendency to disappear once they fall out of the directory cache.

When rclone mount is invoked on Unix with --daemon flag, the main rclone program will wait for the background mount to become ready or until the timeout specified by the --daemon-wait flag. On Linux it can check mount status using ProcFS so the flag in fact sets maximum time to wait, while the real wait can be less. On macOS / BSD the time to wait is constant and the check is performed only at the end. We advise you to set wait time on macOS reasonably.

Only supported on Linux, FreeBSD, OS X and Windows at the moment.

rclone @ vs rclone sync/copy

File systems expect things to be 100% reliable, whereas cloud storage systems are a long way from 100% reliable. The rclone sync/copy commands cope with this with lots of retries. However rclone @ can't use retries in the same way without making local copies of the uploads. Look at the VFS File Caching for solutions to make @ more reliable.

Attribute caching

You can use the flag --attr-timeout to set the time the kernel caches the attributes (size, modification time, etc.) for directory entries.

The default is 1s which caches files just long enough to avoid too many callbacks to rclone from the kernel.

In theory 0s should be the correct value for filesystems which can change outside the control of the kernel. However this causes quite a few problems such as rclone using too much memory, rclone not serving files to samba and excessive time listing directories.

The kernel can cache the info about a file for the time given by --attr-timeout. You may see corruption if the remote file changes length during this window. It will show up as either a truncated file or a file with garbage on the end. With --attr-timeout 1s this is very unlikely but not impossible. The higher you set --attr-timeout the more likely it is. The default setting of "1s" is the lowest setting which mitigates the problems above.

If you set it higher (10s or 1m say) then the kernel will call back to rclone less often making it more efficient, however there is more chance of the corruption issue above.

If files don't change on the remote outside of the control of rclone then there is no chance of corruption.

This is the same as setting the attr_timeout option in mount.fuse.

Filters

Note that all the rclone filters can be used to select a subset of the files to be visible in the mount.

systemd

When running rclone @ as a systemd service, it is possible to use Type=notify. In this case the service will enter the started state after the mountpoint has been successfully set up. Units having the rclone @ service specified as a requirement will see all files and folders immediately in this mode.

Note that systemd runs mount units without any environment variables including PATH or HOME. This means that tilde (~) expansion will not work and you should provide --config and --cache-dir explicitly as absolute paths via rclone arguments. Since mounting requires the fusermount program, rclone will use the fallback PATH of /bin:/usr/bin in this scenario. Please ensure that fusermount is present on this PATH.

Rclone as Unix mount helper

The core Unix program /bin/mount normally takes the -t FSTYPE argument then runs the /sbin/mount.FSTYPE helper program passing it mount options as -o key=val,... or --opt=.... Automount (classic or systemd) behaves in a similar way.

rclone by default expects GNU-style flags --key val. To run it as a mount helper you should symlink rclone binary to /sbin/mount.rclone and optionally /usr/bin/rclonefs, e.g. ln -s /usr/bin/rclone /sbin/mount.rclone. rclone will detect it and translate command-line arguments appropriately.

Now you can run classic mounts like this:

mount sftp1:subdir /mnt/data -t rclone -o vfs_cache_mode=writes,sftp_key_file=/path/to/pem

or create systemd mount units:

# /etc/systemd/system/mnt-data.mount
[Unit]
Description=Mount for /mnt/data
[Mount]
Type=rclone
What=sftp1:subdir
Where=/mnt/data
Options=rw,_netdev,allow_other,args2env,vfs-cache-mode=writes,config=/etc/rclone.conf,cache-dir=/var/rclone

optionally accompanied by systemd automount unit

# /etc/systemd/system/mnt-data.automount
[Unit]
Description=AutoMount for /mnt/data
[Automount]
Where=/mnt/data
TimeoutIdleSec=600
[Install]
WantedBy=multi-user.target

or add in /etc/fstab a line like

sftp1:subdir /mnt/data rclone rw,noauto,nofail,_netdev,x-systemd.automount,args2env,vfs_cache_mode=writes,config=/etc/rclone.conf,cache_dir=/var/cache/rclone 0 0

or use classic Automountd. Remember to provide explicit config=...,cache-dir=... as a workaround for mount units being run without HOME.

Rclone in the mount helper mode will split -o argument(s) by comma, replace _ by - and prepend -- to get the command-line flags. Options containing commas or spaces can be wrapped in single or double quotes. Any inner quotes inside outer quotes of the same type should be doubled.

Mount option syntax includes a few extra options treated specially:

  • env.NAME=VALUE will set an environment variable for the mount process. This helps with Automountd and Systemd.mount which don't allow setting custom environment for mount helpers. Typically you will use env.HTTPS_PROXY=proxy.host:3128 or env.HOME=/root
  • command=cmount can be used to run cmount or any other rclone command rather than the default mount.
  • args2env will pass mount options to the mount helper running in background via environment variables instead of command line arguments. This allows to hide secrets from such commands as ps or pgrep.
  • vv... will be transformed into appropriate --verbose=N
  • standard mount options like x-systemd.automount, _netdev, nosuid and alike are intended only for Automountd and ignored by rclone.