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SSHFS(1)			 User Commands			      SSHFS(1)

NAME
       SSHFS - filesystem client based on SSH

SYNOPSIS
       To mount	a filesystem:

	  sshfs	[user@]host:[dir] mountpoint [options]

       If  host	 is  a numeric IPv6 address, it	needs to be enclosed in	square
       brackets.

       To unmount it:

	  fusermount3 -u mountpoint   #	Linux
	  umount mountpoint	      #	OS X, FreeBSD

DESCRIPTION
       SSHFS allows you	to mount a remote  filesystem  using  SSH  (more  pre-
       cisely,	the  SFTP subsystem). Most SSH servers support and enable this
       SFTP access by default, so SSHFS	is very	simple to use -	there's	 noth-
       ing to do on the	server-side.

       By  default,  file  permissions are ignored by SSHFS. Any user that can
       access the filesystem will be able to perform any  operation  that  the
       remote server permits - based on	the credentials	that were used to con-
       nect to the server. If this is undesired, local permission checking can
       be enabled with -o default_permissions.

       By  default, only the mounting user will	be able	to access the filesys-
       tem. Access for other users can be enabled by passing  -o  allow_other.
       In this case you	most likely also want to use -o	default_permissions.

       It is recommended to run	SSHFS as regular user (not as root).  For this
       to work the mountpoint must be owned by the user.  If username is omit-
       ted  SSHFS  will	 use  the local	username. If the directory is omitted,
       SSHFS will mount	the (remote) home directory.  If you need to  enter  a
       password	sshfs will ask for it (actually	it just	runs ssh which ask for
       the password if needed).

OPTIONS
       -o opt,[opt...]
	      mount options, see below for details. A a	variety	of SSH options
	      can  be given here as well, see the manual pages for sftp(1) and
	      ssh_config(5).

       -h, --help
	      print help and exit.

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

       -d, --debug
	      print debugging information.

       -p PORT
	      equivalent to '-o	port=PORT'

       -f     do not daemonize,	stay in	foreground.

       -s     Single threaded operation.

       -C     equivalent to '-o	compression=yes'

       -F ssh_configfile
	      specifies	alternative ssh	configuration file

       -1     equivalent to '-o	ssh_protocol=1'

       -o reconnect
	      automatically reconnect to server	if connection is  interrupted.
	      Attempts	to  access files that were opened before the reconnec-
	      tion will	give errors and	need to	be re-opened.

       -o delay_connect
	      Don't immediately	connect	to server, wait	 until	mountpoint  is
	      first accessed.

       -o sshfs_sync
	      synchronous  writes. This	will slow things down, but may be use-
	      ful in some situations.

       -o no_readahead
	      Only read	exactly	the data that was requested, instead of	specu-
	      latively reading more to anticipate the next read	request.

       -o sync_readdir
	      synchronous readdir. This	will slow things down, but may be use-
	      ful in some situations.

       -o workaround=LIST
	      Enable the specified workaround. See the Caveats	section	 below
	      for some additional information. Possible	values are:

	      rename Emulate  overwriting an existing file by deleting and re-
		     naming.

	      renamexdev
		     Make rename fail with EXDEV instead of the	default	 EPERM
		     to	allow moving files across remote filesystems.

	      truncate
		     Work around servers that don't support truncate by	coping
		     the whole file, truncating	it  locally,  and  sending  it
		     back.

	      fstat  Work  around broken servers that don't support fstat() by
		     using stat	instead.

	      buflimit
		     Work around OpenSSH "buffer fillup" bug.

	      createmode
		     Work around broken	servers	that  produce  an  error  when
		     passing  a	 non-zero  mode	to create, by always passing a
		     mode of 0.

	      readdir
		     Work around file manager used that	keeps dir  open	 while
		     user  add/remove  files/dirs, that	produce	an error - all
		     dirs become empty for a while  or	until  remount.	  This
		     happen  because  handle  cached after opendir() but read-
		     dir() does	not use	offset.	 Workaround converts readdir()
		     into  "getdir()": opendir() and releasedir() not exported
		     to	fuse; offset set to 0.

       -o idmap=TYPE
	      How to map remote	UID/GIDs to local values. Possible values are:

	      none   no	translation of the ID space (default).

	      user   map the UID/GID of	the remote  user  to  UID/GID  of  the
		     mounting user.

	      file   translate	UIDs/GIDs based	upon the contents of --uidfile
		     and --gidfile.

       -o uidfile=FILE
	      file containing username:uid mappings for	-o idmap=file

       -o gidfile=FILE
	      file containing groupname:gid mappings for -o idmap=file

       -o nomap=TYPE
	      with idmap=file, how to handle missing mappings:

	      ignore don't do any re-mapping

	      error  return an error (default)

       -o ssh_command=CMD
	      execute CMD instead of 'ssh'

       -o ssh_protocol=N
	      ssh protocol to use (default: 2)

       -o sftp_server=SERV
	      path to sftp server or subsystem (default: sftp)

       -o directport=PORT
	      directly connect to PORT bypassing ssh

       -o passive
	      communicate over stdin and stdout	bypassing network. Useful  for
	      mounting	local filesystem on the	remote side.  An example using
	      dpipe command would be dpipe /usr/lib/openssh/sftp-server	=  ssh
	      RemoteHostname  sshfs :/directory/to/be/shared ~/mnt/src -o pas-
	      sive

       -o disable_hardlink
	      With this	option set, attempts to	call link(2)  will  fail  with
	      error code ENOSYS.

       -o transform_symlinks
	      transform	absolute symlinks on remote side to relative symlinks.
	      This means that if e.g. on the server  side  /foo/bar/com	 is  a
	      symlink  to  /foo/blub,  SSHFS will transform the	link target to
	      ../blub on the client side.

       -o follow_symlinks
	      follow symlinks on the server,  i.e.  present  them  as  regular
	      files  on	 the client. If	a symlink is dangling (i.e, the	target
	      does not exist) the behavior depends on the remote server	-  the
	      entry may	appear as a symlink on the client, or it may appear as
	      a	regular	file that cannot be accessed.

       -o no_check_root
	      don't check for existence	of 'dir' on server

       -o password_stdin
	      read password from stdin (only for pam_mount!)

       -o dir_cache=BOOL
	      Enables (yes) or disables	(no) the SSHFS directory  cache.   The
	      directory	 cache	holds the names	of directory entries. Enabling
	      it allows	readdir(3) system calls	to be processed	 without  net-
	      work access.

       -o dcache_max_size=N
	      sets the maximum size of the directory cache.

       -o dcache_timeout=N
	      sets timeout for directory cache in seconds.

       -o dcache_{stat,link,dir}_timeout=N
	      sets  separate timeout for {attributes, symlinks,	names} in  the
	      directory	cache.

       -o dcache_clean_interval=N
	      sets the interval	for automatic cleaning of the directory	cache.

       -o dcache_min_clean_interval=N
	      sets the interval	for forced cleaning  of	 the  directory	 cache
	      when full.

       -o direct_io
	      This  option disables the	use of page cache (file	content	cache)
	      in the kernel for	this filesystem.  This has several affects:

	      1. Each read() or	write()	system call will initiate one or  more
		 read or write operations, data	will not be cached in the ker-
		 nel.

	      2. The return value of the read()	and write() system calls  will
		 correspond  to	the return values of the read and write	opera-
		 tions.	This is	useful for example if the  file	 size  is  not
		 known in advance (before reading it).	e.g. /proc filesystem

       -o max_conns=N
	      sets  the	maximum	number of simultaneous SSH connections to use.
	      Each connection is established with a separate SSH process.  The
	      primary purpose of this feature is to improve the	responsiveness
	      of the file system during	large file transfers. When using  more
	      than once	connection, the	password_stdin and passive options can
	      not be used, and the buflimit workaround is not supported.

       In addition, SSHFS accepts several options common to all	FUSE file sys-
       tems.  These  are  described  in	the mount.fuse manpage (look for "gen-
       eral", "libfuse specific", and "high-level API" options).

CAVEATS	/ WORKAROUNDS
   Hardlinks
       If the SSH server supports the hardlinks	extension,  SSHFS  will	 allow
       you to create hardlinks.	However, hardlinks will	always appear as indi-
       vidual files when seen through an SSHFS mount, i.e. they	will appear to
       have different inodes and an st_nlink value of 1.

   Rename
       Some  SSH servers do not	support	atomically overwriting the destination
       when renaming a file. In	this case you will get an error	when  you  at-
       tempt to	rename a file and the destination already exists. A workaround
       is to first remove the destination file,	and then do the	rename.	 SSHFS
       can  do	this  automatically  if	you call it with -o workaround=rename.
       However,	in this	case it	is still possible that someone (or  something)
       recreates  the  destination file	after SSHFS has	removed	it, but	before
       SSHFS had the time to rename the	old file. In  this  case,  the	rename
       will still fail.

   Permission denied when moving files across remote filesystems
       Most  SFTP  servers return only a generic "failure" when	failing	to re-
       name across filesystem boundaries  (EXDEV).   sshfs  normally  converts
       this  generic failure to	a permission denied error (EPERM).  If the op-
       tion -o workaround=renamexdev is	given, generic failures	will  be  con-
       sidered EXDEV errors which will make programs like mv(1)	attempt	to ac-
       tually move the file after the failed rename.

   SSHFS hangs for no apparent reason
       In some cases, attempts to access the SSHFS mountpoint may freeze if no
       filesystem activity has occured for some	time. This is typically	caused
       by the SSH connection being dropped because of inactivity without SSHFS
       being  informed	about that. As a workaround, you can try to mount with
       -o ServerAliveInterval=15. This will force the SSH connection  to  stay
       alive even if you have no activity.

   SSHFS hangs after the connection was	interrupted
       By default, network operations in SSHFS run without timeouts, mirroring
       the default behavior of SSH itself. As a	consequence, if	the connection
       to the remote host is interrupted (e.g. because a network cable was re-
       moved), operations on files or directories under	 the  mountpoint  will
       block  until  the  connection  is  either restored or closed altogether
       (e.g. manually).	 Applications that try to access such files or	direc-
       tories will generally appear to "freeze"	when this happens.

       If  it  is  acceptable  to  discard data	being read or written, a quick
       workaround is to	kill the responsible sshfs process,  which  will  make
       any blocking operations on the mounted filesystem error out and thereby
       "unfreeze" the relevant applications. Note that force  unmounting  with
       fusermount  -zu,	on the other hand, does	not help in this case and will
       leave read/write	operations in the blocking state.

       For a more automatic solution, one can  use  the	 -o  ServerAliveInter-
       val=15 option mentioned above, which will drop the connection after not
       receiving a response for	3 * 15 = 45 seconds from the remote  host.  By
       also  supplying	-o  reconnect,	one  can ensure	that the connection is
       re-established as soon as possible afterwards.  As  before,  this  will
       naturally lead to loss of data that was in the process of being read or
       written at the time when	the connection was interrupted.

MOUNTING FROM /ETC/FSTAB
       To mount	an SSHFS filesystem from /etc/fstab, simply use	sshfs` as  the
       file  system  type.  (For  backwards  compatibility,  you  may also use
       ``fuse.sshfs).

SEE ALSO
       The mount.fuse(8) manpage.

GETTING	HELP
       If you need help, please	ask on the  <fuse-sshfs@lists.sourceforge.net>
       mailing		      list		  (subscribe		    at
       https://lists.sourceforge.net/lists/listinfo/fuse-sshfs).

       Please	report	 any   bugs   on   the	 GitHub	  issue	  tracker   at
       https://github.com/libfuse/libfuse/issues.

AUTHORS
       SSHFS is	currently maintained by	Nikolaus Rath <Nikolaus@rath.org>, and
       was created by Miklos Szeredi <miklos@szeredi.hu>.

       This  man  page	was  originally	  written   by	 Bartosz   Fenski   <-
       fenio@debian.org>  for the Debian GNU/Linux distribution	(but it	may be
       used by others).

								      SSHFS(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | CAVEATS / WORKAROUNDS | MOUNTING FROM /ETC/FSTAB | SEE ALSO | GETTING HELP | AUTHORS

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