1NTFS-3G(8) System Manager's Manual NTFS-3G(8)
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6 ntfs-3g - Third Generation Read/Write NTFS Driver
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9 ntfs-3g [-o option[,...]] volume mount_point
10 mount -t ntfs-3g [-o option[,...]] volume mount_point
11 lowntfs-3g [-o option[,...]] volume mount_point
12 mount -t lowntfs-3g [-o option[,...]] volume mount_point
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15 ntfs-3g is an NTFS driver, which can create, remove, rename, move
16 files, directories, hard links, and streams; it can read and write
17 files, including streams, sparse files and transparently compressed
18 files; it can handle special files like symbolic links, devices, and
19 FIFOs; moreover it provides standard management of file ownership and
20 permissions, including POSIX ACLs.
21 It comes in two variants ntfs-3g and lowntfs-3g with a few differences
23 mentioned below in relevant options descriptions.
24 The volume to be mounted can be either a block device or an image file,
26 either by using the mount command or starting the drive.
27 Windows hibernation and fast restarting
29 On computers which can be dual-booted into Windows or Linux, Windows
30 has to be fully shut down before booting into Linux, otherwise the NTFS
31 file systems on internal disks may be left in an inconsistent state and
32 changes made by Linux may be ignored by Windows.
33 So, Windows may not be left in hibernation when starting Linux, in or‐
35 der to avoid inconsistencies. Moreover, the fast restart feature avail‐
36 able on recent Windows systems has to be disabled. This can be achieved
37 by issuing as an Administrator the Windows command which disables both
38 hibernation and fast restarting :
39 powercfg /h off
41 If either Windows is hibernated or its fast restart is enabled, parti‐
43 tions on internal disks are forced to be mounted in read-only mode.
44 Access Handling and Security
46 By default, files and directories are owned by the effective user and
47 group of the mounting process, and everybody has full read, write, exe‐
48 cution and directory browsing permissions. You can also assign permis‐
49 sions to a single user by using the uid and/or the gid options together
50 with the umask, or fmask and dmask options.
51 Doing so, all Windows users have full access to the files created by
53 ntfs-3g.
54 But, by setting the permissions option, you can benefit from the full
56 ownership and permissions features as defined by POSIX. Moreover, by
57 defining a Windows-to-Linux user mapping, the ownerships and permis‐
58 sions are even applied to Windows users and conversely.
59 If ntfs-3g is set setuid-root then non-root users will be also able to
61 mount volumes.
62 Windows Filename Compatibility
64 NTFS supports several filename namespaces: DOS, Win32 and POSIX. While
65 the ntfs-3g driver handles all of them, it always creates new files in
66 the POSIX namespace for maximum portability and interoperability rea‐
67 sons. This means that filenames are case sensitive and all characters
68 are allowed except '/' and '\0'. This is perfectly legal on Windows,
69 though some application may get confused. The option windows_names may
70 be used to apply Windows restrictions to new file names.
71 Alternate Data Streams (ADS)
73 NTFS stores all data in streams. Every file has exactly one unnamed
74 data stream and can have many named data streams. The size of a file
75 is the size of its unnamed data stream. By default, ntfs-3g will only
76 read the unnamed data stream.
77 By using the option streams_interface=windows, with the ntfs-3g driver
79 (not possible with lowntfs-3g), you will be able to read any named data
80 streams, simply by specifying the stream name after a colon. For exam‐
81 ple:
82 cat some.mp3:artist
84 Named data streams act like normal files, so you can read from them,
86 write to them and even delete them (using rm). You can list all the
87 named data streams a file has by getting the ntfs.streams.list extended
88 attribute.
89
91 Below is a summary of the options that ntfs-3g accepts.
92 acl Enable setting Posix ACLs on created files and use them for ac‐
94 cess control. This option is only available on specific builds.
95 It is set by default when a user mapping file is present and the
96 permissions mount option is not set.
97 allow_other
99 This option overrides the security measure restricting file ac‐
100 cess to the user mounting the filesystem. This option is only
101 allowed to root, but this restriction can be overridden by the
102 user_allow_other option in the /etc/fuse.conf file.
103 atime, noatime, relatime
105 The atime option updates inode access time for each access.
106 The noatime option disables inode access time updates, which can
108 speed up file operations and prevent sleeping (notebook) disks
109 spinning up too often thus saving energy and disk lifetime.
110 The relatime option is very similar to noatime. It updates in‐
112 ode access times relative to modify or change time. The access
113 time is only updated if the previous access time was earlier
114 than the current modify or change time. Unlike noatime this op‐
115 tion doesn't break applications that need to know if a file has
116 been read since the last time it was modified. This is the de‐
117 fault behaviour.
118 big_writes
120 This option prevents fuse from splitting write buffers into 4K
121 chunks, enabling big write buffers to be transferred from the
122 application in a single step (up to some system limit, generally
123 128K bytes).
124 compression
126 This option enables creating new transparently compressed files
127 in directories marked for compression. A directory is marked for
128 compression by setting the bit 11 (value 0x00000800) in its Win‐
129 dows attribute. In such a directory, new files are created com‐
130 pressed and new subdirectories are themselves marked for com‐
131 pression. The option and the flag have no effect on existing
132 files. Currently this is the default option.
133 debug Makes ntfs-3g (or lowntfs-3g) to print a lot of debug output
135 from libntfs-3g and FUSE.
136 delay_mtime[= value]
138 Only update the file modification time and the file change time
139 of a file when it is closed or when the indicated delay since
140 the previous update has elapsed. The argument is a number of
141 seconds, with a default value of 60. This is mainly useful for
142 big files which are kept open for a long time and written to
143 without changing their size, such as databases or file system
144 images mounted as loop.
145 dmask=value
147 Set the bitmask of the directory permissions that are not
148 present. The value is given in octal. The default value is 0
149 which means full access to everybody.
150 efs_raw
152 This option should only be used in backup or restore situation.
153 It changes the apparent size of files and the behavior of read
154 and write operation so that encrypted files can be saved and re‐
155 stored without being decrypted. The user.ntfs.efsinfo extended
156 attribute has also to be saved and restored for the file to be
157 decrypted.
158 fmask=value
160 Set the bitmask of the file permissions that are not present.
161 The value is given in octal. The default value is 0 which means
162 full access to everybody.
163 force This option is obsolete. It has been superseded by the recover
165 and norecover options.
166 hide_dot_files
168 Set the hidden flag in the NTFS attribute for created files and
169 directories whose first character of the name is a dot. Such
170 files and directories normally do not appear in directory list‐
171 ings, and when the flag is set they do not appear in Windows di‐
172 rectory displays either. When a file is renamed or linked with
173 a new name, the hidden flag is adjusted to the latest name.
174 hide_hid_files
176 Hide the hidden files and directories in directory listings, the
177 hidden files and directories being the ones whose NTFS attribute
178 have the hidden flag set. The hidden files will not be selected
179 when using wildcards in commands, but all files and directories
180 remain accessible by full name, for example you can always dis‐
181 play the Windows trash bin directory by : "ls -ld '$RECY‐
182 CLE.BIN'".
183 ignore_case (only with lowntfs-3g)
185 Ignore character case when accessing a file (FOO, Foo, foo, etc.
186 designate the same file). All files are displayed with lower
187 case in directory listings.
188 inherit
190 When creating a new file, set its initial protections according
191 to inheritance rules defined in parent directory. These rules
192 deviate from Posix specifications, but yield a better Windows
193 compatibility. The permissions (or **acl**) option or a valid
194 user mapping file is required for this option to be effective.
195 locale=value
197 This option can be useful when wanting a language specific lo‐
198 cale environment. It is however discouraged as it leads to
199 files with untranslatable characters to not be visible.
200 max_read=value
202 With this option the maximum size of read operations can be set.
203 The default is infinite. Note that the size of read requests is
204 limited anyway by the system (usually to 128kbyte).
205 no_def_opts
207 By default ntfs-3g acts as if silent (ignore permission errors
208 when permissions are not enabled), allow_other (allow any user
209 to access files) and nonempty (allow mounting on non-empty di‐
210 rectories) were set, and no_def_opts cancels these default op‐
211 tions.
212 no_detach
214 Makes ntfs-3g to not detach from terminal and print some debug
215 output.
216 nocompression
218 This option disables creating new transparently compressed files
219 in directories marked for compression. Existing compressed files
220 can still be read and updated.
221 norecover
223 Do not try to mount a partition which was not unmounted properly
224 by Windows.
225 permissions
227 Set standard permissions on created files and use standard ac‐
228 cess control. This option is set by default when a user mapping
229 file is present.
230 posix_nlink
232 Compute the count of hard links of a file or directory according
233 to the POSIX specifications. When this option is not set, a
234 count of 1 is set for directories, and the short name of files
235 is accounted for. Using the option entails some penalty as the
236 count is not stored and has to be computed.
237 recover
239 Recover and try to mount a partition which was not unmounted
240 properly by Windows. The Windows logfile is cleared, which may
241 cause inconsistencies. Currently this is the default option.
242 remove_hiberfile
244 When the NTFS volume is hibernated, a read-write mount is denied
245 and a read-only mount is forced. One needs either to resume Win‐
246 dows and shutdown it properly, or use this option which will re‐
247 move the Windows hibernation file. Please note, this means that
248 the saved Windows session will be completely lost. Use this op‐
249 tion under your own responsibility.
250 ro Mount the filesystem read-only. Useful if Windows is hibernated
252 or the NTFS journal file is unclean.
253 show_sys_files
255 Show the metafiles in directory listings. Otherwise the default
256 behaviour is to hide the metafiles, which are special files used
257 to store the NTFS structure. Please note that even when this op‐
258 tion is specified, "$MFT" may not be visible due to a glibc bug.
259 Furthermore, irrespectively of show_sys_files, all files are ac‐
260 cessible by name, for example you can always do "ls -l '$Up‐
261 Case'".
262 silent Do nothing, without returning any error, on chmod and chown op‐
264 erations and on permission checking errors, when the permissions
265 option is not set and no user mapping file is defined. This op‐
266 tion is on by default, and when set off (through option
267 no_def_opts) ownership and permissions parameters have to be
268 set.
269 special_files=mode
271 This option selects a mode for representing a special file to be
272 created (symbolic link, socket, fifo, character or block de‐
273 vice). The mode can be interix or wsl, and existing files in ei‐
274 ther mode are recognized irrespective of the selected mode. In‐
275 terix is the traditional mode, used by default, and wsl is in‐
276 teroperable with Windows WSL, but it is not compatible with Win‐
277 dows versions earlier than Windows 10. Neither mode are inter‐
278 operable with Windows.
279 streams_interface=mode
281 This option controls how the user can access Alternate Data
282 Streams (ADS) or in other words, named data streams. The mode
283 can be set to one of none, windows or xattr. If the option is
284 set to none, the user will have no access to the named data
285 streams. If it is set to windows (not possible with lowntfs-3g),
286 then the user can access them just like in Windows (eg. cat
287 file:stream). If it's set to xattr, then the named data streams
288 are mapped to extended attributes and a user can manipulate them
289 using {get,set}fattr utilities. The default is xattr.
290 uid=value and gid=value
292 Set the owner and the group of files and directories. The values
293 are numerical. The defaults are the uid and gid of the current
294 process.
295 umask=value
297 Set the bitmask of the file and directory permissions that are
298 not present. The value is given in octal. The default value is 0
299 which means full access to everybody.
300 usermapping=file-name
302 Use file file-name as the user mapping file instead of the de‐
303 fault .NTFS-3G/UserMapping. If file-name defines a full path,
304 the file must be located on a partition previously mounted. If
305 it defines a relative path, it is interpreted relative to the
306 root of NTFS partition being mounted.
307 When a user mapping file is defined, the options uid=, gid=,
309 umask=, fmask=, dmask= and silent are ignored.
310 user_xattr
312 Same as streams_interface=xattr.
313 windows_names
315 This option prevents files, directories and extended attributes
316 to be created with a name not allowed by windows, because
317 - it contains some not allowed character,
319 - or the last character is a space or a dot,
320 - or the name is reserved.
321 The forbidden characters are the nine characters " * / : < > ? \
323 | and those whose code is less than 0x20, and the reserved names
324 are CON, PRN, AUX, NUL, COM1..COM9, LPT1..LPT9, with no suffix
325 or followed by a dot.
326 Existing such files can still be read (and renamed).
328
330 NTFS uses specific ids to record the ownership of files instead of the
331 uid (user id) and gid (group id) used by Linux. As a consequence a map‐
332 ping between the ids has to be defined for ownerships to be recorded
333 into NTFS files and recognized.
334 By default, this mapping is fetched from the file .NTFS-3G/UserMapping
336 located in the NTFS partition. The option usermapping= may be used to
337 define another location. When the option **permissions** is set and no
338 mapping file is found, a default mapping is used.
339 Each line in the user mapping file defines a mapping. It is organized
341 in three fields separated by colons. The first field identifies a uid,
342 the second field identifies a gid and the third one identifies the cor‐
343 responding NTFS id, known as a SID. The uid and the gid are optional
344 and defining both of them for the same SID is not recommended.
345 If no interoperation with Windows is needed, you can use the option
347 permissions to define a standard mapping. Alternately, you may define
348 your own mapping by setting a single default mapping with no uid and
349 gid. In both cases, files created on Linux will appear to Windows as
350 owned by a foreign user, and files created on Windows will appear to
351 Linux as owned by root. Just copy the example below and replace the 9
352 and 10-digit numbers by any number not greater than 4294967295. The re‐
353 sulting behavior is the same as the one with the option permission set
354 with no ownership option and no user mapping file available.
355 ::S-1-5-21-3141592653-589793238-462643383-10000
357 If a strong interoperation with Windows is needed, the mapping has to
359 be defined for each user and group known to both system, and the SIDs
360 used by Windows has to be collected. This will lead to a user mapping
361 file like :
362 john::S-1-5-21-3141592653-589793238-462643383-1008
364 mary::S-1-5-21-3141592653-589793238-462643383-1009
365 :smith:S-1-5-21-3141592653-589793238-462643383-513
366 ::S-1-5-21-3141592653-589793238-462643383-10000
367 The utility ntfsusermap may be used to create such a user mapping file.
370
372 Mount /dev/sda1 to /mnt/windows:
373 ntfs-3g /dev/sda1 /mnt/windows
375 or
376 mount -t ntfs-3g /dev/sda1 /mnt/windows
377 Mount the ntfs data partition /dev/sda3 to /mnt/data with standard
379 Linux permissions applied :
380 ntfs-3g -o permissions /dev/sda3 /mnt/data
382 or
383 mount -t ntfs-3g -o permissions /dev/sda3 /mnt/data
384 Read-only mount /dev/sda5 to /home/user/mnt and make user with uid 1000
386 to be the owner of all files:
387 ntfs-3g /dev/sda5 /home/user/mnt -o ro,uid=1000
389 /etc/fstab entry for the above (the sixth and last field has to be zero
391 to avoid a file system check at boot time) :
392 /dev/sda5 /home/user/mnt ntfs-3g ro,uid=1000 0 0
394 Unmount /mnt/windows:
396 umount /mnt/windows
398
401 To facilitate the use of the ntfs-3g driver in scripts, an exit code is
402 returned to give an indication of the mountability status of a volume.
403 Value 0 means success, and all other ones mean an error. The unique er‐
404 ror codes are documented in the ntfs-3g.probe(8) manual page.
405
407 Please see
408 https://github.com/tuxera/ntfs-3g/wiki/NTFS-3G-FAQ
410 for common questions and known issues. If you would find a new one in
412 the latest release of the software then please post an ntfs-3g issue
413 describing it in detail so that the development team can be aware of
414 the issue and take care of it:
415 https://github.com/tuxera/ntfs-3g/issues
417
420 ntfs-3g was based on and a major improvement to ntfsmount and libntfs
421 which were written by Yura Pakhuchiy and the Linux-NTFS team. The im‐
422 provements were made, the ntfs-3g project was initiated and currently
423 led by long time Linux-NTFS team developer Szabolcs Szakacsits
424 (szaka@tuxera.com).
425
427 Several people made heroic efforts, often over five or more years which
428 resulted the ntfs-3g driver. Most importantly they are Anton Alta‐
429 parmakov, Jean-Pierre André, Erik Larsson, Richard Russon, Szabolcs
430 Szakacsits, Yura Pakhuchiy, Yuval Fledel, and the author of the ground‐
431 breaking FUSE filesystem development framework, Miklos Szeredi.
432
434 ntfs-3g.probe(8), ntfsprogs(8), attr(5), getfattr(1)
435ntfs-3g 2022.10.3 Aug 2021 NTFS-3G(8)