1mount.davfs(8)                       1.6.1                      mount.davfs(8)
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NAME

6       mount.davfs - Mount a WebDAV resource as davfs2 file system
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SYNOPSIS

11       mount.davfs [-h | --help] [-V | --version]
12       mount {dir | webdavserver}
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SYNOPSIS (root only)

17       mount -t davfs [-o option[,...]] webdavserver dir
18       mount.davfs [-o option[,...]] webdavserver dir
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DESCRIPTION

23       mount.davfs  allows you to mount the WebDAV resource identified by web‐
24       davserver into the local filesystem at dir.  WebDAV is an extension  to
25       HTTP  that allows remote, collaborative authoring of Web resources, de‐
26       fined in RFC 4918.  mount.davfs is part of davfs2.
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29       davfs2 allows documents on a remote Web server to be edited using stan‐
30       dard  applications.  For  example,  a  remote Web site could be updated
31       in-place using the same development tools that  initially  created  the
32       site.   Or  you may use a WebDAV resource for documents you want to ac‐
33       cess and edited from different locations.
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35
36       davfs2 supports TLS/SSL (if the neon library supports it) and  proxies.
37       mount.davfs  runs as a daemon in userspace. It integrates into the vir‐
38       tual file system by the fuse kernel files system.  Currently  FUSE_KER‐
39       NEL_VERSION 7 is supported.
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42       mount.davfs  is  usually invoked by the mount(8) command when using the
43       -t davfs option. After mounting it runs as a  daemon.  To  unmount  the
44       umount(8) command is used.
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47       webdavserver  is  the  URL  of the server. It must at least contain the
48       host name. It may additionally contain the scheme,  the  port  and  the
49       path.   Missing components are set to sensible default values. The path
50       component must not be %-encoded, but when entering the URL at the  com‐
51       mand  line  or  in  /etc/fstab the escaping rules of the shell or fstab
52       must be obeyed.
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55       dir is the mountpoint where the WebDAV resource is mounted on.  It  may
56       be an absolute or relative path.
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58
59       fstab may be used to define mounts and mount options as usual. In place
60       of the device the url of the WebDAV server must be  given.  There  must
61       not be more than one entry in fstab for every mountpoint.
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OPTIONS

66       -V --version
67              Output version.
68
69
70       -h --help
71              Print a help message.
72
73
74       -o     A  comma-separated list defines mount options to be used. Avail‐
75              able options are:
76
77
78              [no]auto
79                     Can (not) be mounted with mount -a.
80                     Default: auto.
81
82
83              comment=some comment
84                     This option is ignored by mount.davfs but other  programs
85                     may require it to be present in fstab.
86
87
88              conf=absolute path
89                     An  alternative  user  configuration file. This option is
90                     intended for cases where the default  user  configuration
91                     file in the users home directory can not be used.
92                     Default: ~/.davfs2/davfs2.conf
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94
95              [no]dev
96                     (Do  not)  interpret character or block  special  devices
97                     on the file system.  This option  is  only  included  for
98                     compatibility  with  the mount(8) program. It will always
99                     be set to nodev
100
101
102              dir_mode=mode
103                     The default mode bits for directories in the mounted file
104                     system.  Value  given in octal. s-bits for user and group
105                     are always silently ignored.
106                     Default: calculated from the umask of the mounting  user;
107                     an x-bit is associated to every r-bit in u-g-o.
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109
110              [no]exec
111                     (Do   not)  allow   execution   of  any  binaries  on the
112                     mounted file system.
113                     Default: exec. (When mounting as an  ordinary  user,  the
114                     mount(8) program will set the default to noexec.)
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116
117              file_mode=mode
118                     The  default mode bits for files in the mounted file sys‐
119                     tem. Value given in octal. s-bits for user and group  are
120                     always silently ignored.
121                     Default:  calculated from the umask of the mounting user;
122                     no x-bits are set for files.
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124
125              gid=group
126                     The group the mounted file system belongs to. It may be a
127                     numeric  ID  or  a  group name. The mounting user, if not
128                     root, must be member of this group.
129                     Default: the primary group of the mounting user.
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131
132              [no]grpid
133                     When this option is set a newly created  file  will  take
134                     the  group  id  of  the directory in which it is created.
135                     This will also apply to all files that are on the  server
136                     and not in the local cache. (That is because the group id
137                     is not stored on the server.)
138                     If the group id of the directory is root this  option  is
139                     ignored.
140                     Default: nogrpid.
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142
143              [no]_netdev
144                     The file system needs a (no) network connection for oper‐
145                     ation. This information allows the  operating  system  to
146                     handle  the file system properly at system start and when
147                     the network is shut down.
148                     Default: _netdev
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150
151              ro     Mount the file system read-only.
152                     Default: rw.
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154
155              rw     Mount the file system read-write.
156                     Default: rw.
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158
159              [no]suid
160                     Do not allow set-user-identifier or  set-group-identifier
161                     bits  to  take  effect.  This option is only included for
162                     compatibility with the mount program. It will  always  be
163                     set to nosuid.
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165
166              [no]user
167                     (Do  not)  allow   an   ordinary  user  to mount the file
168                     system. The name of the mounting user is written to  mtab
169                     so that he can unmount the file system again. Option user
170                     implies the options  noexec,  nosuid  and  nodev  (unless
171                     overridden by subsequent options). This option makes only
172                     sense when set in fstab.
173                     Default: ordinary users are not allowed to mount.
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175
176              users  Like user, but any user is allowed to  unmount  the  file
177                     system, not only the mounting user. This is generally not
178                     recomended.  If the user option  allows  an  unprivileged
179                     user  to mount, but unmounting by the mounting user fails
180                     the users may be a work around.
181                     Default: only the mounting user is allowed to unmount the
182                     file system.
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184
185              uid=user
186                     The owner of the mounted file system. It may be a numeric
187                     ID or a user name.  Only when mounted by root,  this  may
188                     be different from the mounting user.
189                     Default: ID of the mounting user.
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192              username=WebDAV_user
193                     Use  this  name  to  authenticate with the WebDAV server.
194                     This option is intended for use with pam_mount only. When
195                     this  option  is set the credentials in the secrets files
196                     will be ignored. The password will always  be  read  from
197                     stdin,  even when option askauth is set to 0.  Do not use
198                     it in fstab. The username will be visible for everyone in
199                     the output of ps.
200                     Default: no username.
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203

SECURITY POLICY

205       mount.davfs  needs  root privileges for mounting. But running a daemon,
206       that is connected to the internet, with root privileges is  a  security
207       risk.  So  mount.davfs will change its uid and gid when entering daemon
208       mode.
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210
211              When invoked by root mount.davfs will run  as  user  davfs2  and
212              group davfs2. This may be changed in /etc/davfs2/davfs2.conf.
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215              When invoked by an ordinary user it will run with the id of this
216              user and with group davfs2.
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218       As the file system may be mounted over an insecure internet connection,
219       this  increases  the risk that malicious content may be included in the
220       file system. So mount.davfs is slightly more restrictive than mount(8).
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223              Options nosuid and nodev will always be set; even root  can  not
224              change this.
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226
227              For  ordinary  users to be able to mount, they must be member of
228              group davfs2 and there must be an entry in fstab.
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231              When the mount point given in fstab is a relative file name  and
232              the  file  system  is mounted by an unprivileged user, the mount
233              point must lie within the home directory of the mounting user.
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236              If in fstab option uid and/or gid are given,  an  ordinary  user
237              can only mount, if her uid is the one given in option uid and he
238              belongs to the group given in option gid.
239
240       WARNING: If root allows an ordinary user to mount a file system  (using
241       fstab)  this includes the permission to read the associated credentials
242       from /etc/davfs2/secrets as well as the private key of  the  associated
243       client  certificate and the mounting user may get access to this infor‐
244       mation. You should only do this, if you might as well give this  infor‐
245       mation to the user directly.
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URLS AND MOUNT POINTS WITH SPACES

249       Special characters like spaces in pathnames are a mess. They are inter‐
250       preted differently by different programs and protocols, and  there  are
251       different rules for escaping.
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254       In  fstab  spaces  must  be  replaced by a three digit octal escape se‐
255       quence.   Write   http://foo.bar/path\040with\040spaces   instead    of
256       http://foo.bar/path with spaces.
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259       For  the  davfs2.conf  and  the secrets files please see the escape and
260       quotation rules described in the davfs2.conf(5) man page.
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263       On command line you must obey the escaping rules of the shell.
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CACHING

268       mount.davfs tries to reduce HTTP-trafic by caching  and  reusing  data.
269       Information about directories and files are held in memory, while down‐
270       loaded files are cached on disk.
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273       mount.davfs needs to hold a local copy of all open files in  the  cache
274       directory. Please make sure that enough local disk space is available.
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277       mount.davfs will consider cached information about directories and file
278       attributes valid for a configurable time and look up  this  information
279       on  the server only after this time has expired (or there is other evi‐
280       dence that this information is stale). So if somebody else  creates  or
281       deletes files on the server it may take some time before the local file
282       system reflects this.
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285       This will not affect the content of files and directory listings. When‐
286       ever  a  file is opened, the server is looked up for a newer version of
287       the file.  Please consult the manual davfs2.conf(5) to see how can  you
288       configure this according your needs.
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LOCKS, LOST UPDATE PROBLEM AND BACKUP FILES

293       WebDAV introduced locks and mount.davfs uses them by default. This will
294       in most cases prevent two people from changing the same file in  paral‐
295       lel. But not always:
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298              You  might  have  disabled  locks  in /etc/davfs2/davfs2.conf or
299              ~/.davfs2/davfs2.conf.
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302              The server might not support locks (they are not mandatory).
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305              A bad connection might prevent mount.davfs from  refreshing  the
306              lock in time.
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309              Another  WebDAV-client might use your lock (that is not too dif‐
310              ficult and might even happen without intention).
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313       mount.davfs will therefore check if the file has been  changed  on  the
314       the  server  before it uploads a new version. If it finds it impossible
315       to upload the locally changed file, it  will  store  it  in  the  local
316       backup  direcotry lost+found. You should check this directory from time
317       to time and decide what to do with this files.
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320       Sometimes locks held by some client on the server will not be released.
321       Maybe  the  client  crashes  or  the  network  connection  fails.  When
322       mount.davfs finds a file locked on the server, it  will  check  whether
323       the  lock  is held by mount.davfs and the current user, and if so tries
324       to reuse and release it. But this will not always succeed.  So  servers
325       should  automatically  release locks after some time, when they are not
326       refreshed by the client.
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329       WebDAV allows one to lock files that don't exist (to protect  the  name
330       when  a  client  intends to create a new file). This locks will be dis‐
331       played as files with size 0 and last modified date  of  1970-01-01.  If
332       this locks are not released properly mount.davfs may not be able to ac‐
333       cess this files.  You  can  use  cadaver(1)  <http://www.webdav.org/ca
334       daver/> to remove this locks.
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FILE OWNER AND PERMISSIONS

339       davfs2  implements  Unix  permissions  for access control. But changing
340       owner and permissions of a file is only local.  It  is  intended  as  a
341       means  for the owner of the file system, to control whether other local
342       users may acces this file system.
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345       The server does not know about this. From the  servers  point  of  view
346       there  is  just one user (identified by the credentials) connected. An‐
347       other WebDAV-client, connected to the same server, is not  affected  by
348       this local changes.
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351       There  is  one exception: The execute bit on files is stored as a prop‐
352       erty on the sever. You may think of this  property  as  an  information
353       about  the  type  of file rather than a permission. Whether the file is
354       executable on the local system is still controlled by mount options and
355       local permissions.
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358       When  the file system is unmounted, attributes of cached files (includ‐
359       ing owner and permissions) are stored in cache,  as  well  as  the  at‐
360       tributs  of  the  direcotries  they are in. But there is no information
361       stored about directories that do not contain cached files.
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FILES

366       /etc/davfs2/davfs2.conf
367              System wide configuration file.
368
369
370       ~/.davfs2/davfs2.conf
371              Configuration file in the users home directory.The user configu‐
372              ration  takes  precedence over the system wide configuration. If
373              it does not exist, mount.davfs will will create a template file.
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375
376       /etc/davfs2/secrets
377              Holds the credentials for WebDAV servers and the proxy, as  well
378              as  decryption  passwords for client certificates. The file must
379              be read-writable by root only.
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381
382       ~/.davfs2/secrets
383              Holds credentials for WebDAV servers and proxy, as well  as  de‐
384              cryption  passwords  for  client  certificates. The file must be
385              read-writable by the owner only. Credentials are first looked up
386              in  the  home directory of the mounting user. If not found there
387              the system wide secrets file is consulted. If  no  creditentials
388              and  passwords  are  found they are asked from the user interac‐
389              tively  (if  not  disabled).  If  the  file  does   not   exist,
390              mount.davfs will will create a template file.
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392
393       /etc/davfs2/certs
394              You  may store trusted server certificates here, that can not be
395              verified by use of the system wide CA-Certificates. This is use‐
396              ful  when your server uses a selfmade certificate. You must con‐
397              figure  the  servercert  option  in  /etc/davfs2/davfs2.conf  or
398              ~/.davfs2/davfs2.conf  to  use  it.  Certificates must be in PEM
399              format.
400              Be sure to verify the certificate.
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402
403       ~/.davfs2/certs
404              You may store trusted server certificates here, that can not  be
405              verified by use of the system wide CA-Certificates. This is use‐
406              ful when your server uses a selfmade certificate. You must  con‐
407              figure the servercert option in ~/.davfs2/davfs2.conf to use it.
408              Certificates must be in PEM format.
409              Be sure to verify the certificate.
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411
412       /etc/davfs2/certs/private
413              To store client certificates. Certificates must  be  in  PKCS#12
414              format.   You   must   configure   the   clientcert   option  in
415              /etc/davfs2/davfs2.conf or ~/.davfs2/davfs2.conf to use it. This
416              directory must be rwx by root only.
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418
419       ~/.davfs2/certs/private
420              To  store  client  certificates. Certificates must be in PKCS#12
421              format.  You   must   configure   the   clientcert   option   in
422              ~/.davfs2/davfs2.conf  to  use it. This directory must be rwx by
423              the owner only.
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425
426       /var/run/mount.davfs
427              PID-files of running mount.davfs  processes  are  stored  there.
428              This  directory  must  belong to group davfs2 with write permis‐
429              sions for the group and the  sticky-bit  set  (mode  1775).  The
430              PID-files are named after the mount point of the file system.
431
432
433       /var/cache/davfs2
434              System  wide directory for cached files. Used when the file sys‐
435              tem is mounted by root. It must belong do group davfs2 and read,
436              write  and execute bits for group must be set. There is a subdi‐
437              rectory for every mounted file system. The names of this  subdi‐
438              rectories are created from url, mount point and user name.
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440
441       ~/.davfs2/cache
442              Cache  directory in the mounting users home directory. For every
443              mounted WebDAV resource a subdirectory is created.
444
445       mount.davfs will try to create missing directories,  but  it  will  not
446       touch /etc/davfs2.
447
448

ENVIRONMENT

450       https_proxy http_proxy all_proxy
451              If  no  proxy  is defined in the configuration file the value is
452              taken from this environment variables. The proxy  may  be  given
453              with or without scheme and with or without port
454              http_proxy=[http://]foo.bar[:3218]
455              Only used when the mounting user is root.
456
457
458       no_proxy
459              A  comma  separated  list of domain names that shall be accessed
460              directly.  * matches any domain name.  A  domain  name  starting
461              with .  (period) matches all subdomains.
462              Only used when the mounting user is root.
463              Not applied when the proxy is defined in /etc/davfs2.
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465
466

EXAMPLES

468       Non root user (e.g. filomena):
469
470
471       To allow an ordinary user to mount there must be an entry in fstab
472              http://webdav.org/dav   /media/dav   davfs   noauto,user   0   0
473
474
475       If   a   proxy   must   be   used   this   should   be   configured  in
476       /etc/davfs2/davfs2.conf
477              proxy   proxy.mycompany.com:8080
478
479
480       Credentials are stored in /home/filomena/.davfs2/secrets
481              proxy.mycompany.com     filomena  "my secret"
482              /media/dav   webdav-username   password
483
484
485       Now the WebDAV resource may be mounted by user filomena invoking
486              mount /media/dav
487
488
489       and unmounted by user filomena invoking
490              umount /media/dav
491
492
493       Root user only:
494
495
496       Mounts  the  resource  https://asciigirl.com/webdav  at   mount   point
497       /mount/site,   encrypting   all   traffic  with  SSL.  Credentials  for
498       http://webdav.org/dav will be looked up in /etc/davfs2/secrets, if  not
499       found there the user will be asked.
500              mount  -t  davfs  -o  uid=otto,gid=users,mode=775  https://asci
501              igirl.com/webdav /mount/site
502
503
504       Mounts the resource http://linux.org.ar/repos at /dav.
505              mount.davfs            -o            uid=otto,gid=users,mode=775
506              http://linux.org.ar/repos/ /dav
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509

BUGS

511       davfs2 does not support links.
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513       A davfs2 file system cannot be moved with mount --move.
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AUTHORS

518       This  man  page was written by Luciano Bello <luciano@linux.org.ar> for
519       Debian, for version 0.2.3 of davfs2.
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521
522       It has been updated for this version  by  Werner  Baumann  <werner.bau‐
523       mann@onlinhome.de>.
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525
526       davfs2 is developed by Sung Kim <hunkim@gmail.com>.
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528
529       Version  1.0.0  (and  later)  of davfs2 is a complete rewrite by Werner
530       Baumann.
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533

DAVFS2 HOME

535       http://savannah.nongnu.org/projects/davfs2
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538

SEE ALSO

540       umount.davfs(8), davfs2.conf(5), mount(8), umount(8), fstab(5)
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544davfs2                            2020-08-03                    mount.davfs(8)
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