MOUNT.FEDFS(8)						      System Manager's Manual						    MOUNT.FEDFS(8)

NAME

       mount.fedfs - mount a FedFS domain root

SYNOPSIS

       mount.fedfs remotedir localdir [-fhnrsvVw] [-o options]

DESCRIPTION

       RFC  5716  introduces the Federated File System (FedFS, for short).  FedFS is an extensible standardized mechanism by which system adminis-
       trators construct a coherent namespace across multiple file servers using file system referrals.  For further details, see fedfs(7).

       The mount.fedfs(8) command locates FedFS domains by looking for DNS SRV records that advertise file servers  exporting  FedFS  domain  root
       replicas.  The remotedir argument determines what FedFS domain is mounted and what network file system protocol is used.

       The mount.fedfs(8) command sorts the list of available domain root replicas according to the SRV record sorting rules outlined in RFC 2782.
       It attempts to contact each file server appearing in the SRV record list until a mount request succeeds or the end of the SRV  record  list
       is reached.

   Command line arguments
       The first argument, remotedir, is the globally useful name to mount.  Globally useful names are discussed in more detail in fedfs(7).

       The  second  argument,  localdir,  specifies the local directory on which to mount the requested FedFS globally useful name.  As with other
       file systems, localdir must exist on the client for a mount request to succeed.

       The mount.fedfs(8) command converts the specified remotedir and localdir arguments, along with information obtained via DNS SRV queries, to
       arguments  suitable  for  a  local  mount  request.   It  then  forks  and  execs the appropriate file system mount subcommand (such as the
       mount.nfs(8) subcommand) to mount the file server where the domain root resides.

       Because an unmodified file system mount subcommand is used for the actual mount operation, the file system's equivalent	umount	subcommand
       is all that is required to unmount this mount point when it is finished being used.

   Mount option inheritance
       The  Linux  NFS client treats an NFS referral as a server-initiated mount request.  The referring fileserver provides only a list of server
       names and export paths.	The mount options for this new mount are inherited from the new mount point's parent directory on the client.

       As applications proceed deeper into a domain's namespace, they can encounter both file sets to which they have read-only access,  and  file
       sets  to  which they have read-write access.  To allow applications proper access to both types of file sets, typically file-access clients
       mount domain root directories in read-write mode.  All submounts of the domain root are then mounted read-write as well.  Write	access	is
       then controlled by fileservers.

       For  example,  a  domain  root may contain an NFS version 4 referral to an export containing user home directories.  The domain root may be
       exported read-only so file-access clients cannot update it, but user home directories would not be very useful if they could not be written
       to by their owners.  The fileserver continues to employ user credentials to limit access as appropriate.

       Network	file  system  clients  follow  file system referrals as applications encounter them, which is similar to how an automounter works.
       Consider the initial mount of the domain root as if you are mounting a single whole file system, even  though  underneath,  additional  NFS
       mounts come and go as needed.

   Options
       -f, --fake
	      Fake mount.  This option is ignored by mount.fedfs(8) but is passed to the underlying file system mount subcommand.

       -h, --help
	      Print the mount.fedfs(8) usage message and exit.

       -n, --no-mtab
	      Do not update /etc/mtab.	This option is ignored by mount.fedfs(8) but is passed to the underlying file system mount subcommand.

       -o, --options options
	      Specify  mount options for this mount point and all submounts.  These are ignored by mount.fedfs(8) but are passed to the underlying
	      file system mount subcommand.  For further details, refer to mount(8).

       -r, --ro, --read-only
	      Mount the domain root and all submounts read-only.

       -s, --sloppy
	      Tolerate unrecognized mount options.  This is ignored by mount.fedfs(8) but is passed to the underlying file  system  mount  subcom-
	      mand.

       -v, --verbose
	      Report  more  information  during  the  mount process.  This affects mount.fedfs(8) and is also passed to the underlying file system
	      mount subcommand.

       -V, --version
	      Print version information for mount.fedfs(8) and exit.

       -w, --rw, --read-write
	      Mount the domain root and all submounts read-write.  This is the default behavior.

EXAMPLES

       To mount the domain root of the example.net FedFS domain via NFS version 4 automatically, you might add this to your /etc/fstab:

	      /nfs4/example.net   /nfs4/example.net   fedfs  defaults  0  0

       A FedFS domain root can also be mounted with a stand-alone invocation of mount(8):

	      # mount -t fedfs /nfs4/example.net /mnt/fedfs

       This mounts the FedFS domain root for the example.net domain on the client's /mnt/fedfs directory.  A simple

	      # umount /mnt/fedfs

       unmounts it when you are finished with it.

FILES

       /etc/fstab	 filesystem table

       /etc/mtab	 table of mounted file systems

SEE ALSO

       fedfs(7), nfs(5), mount(8), mount.nfs(8)

       RFC 2782 for a discussion of DNS SRV records

       RFC 5661 for a description of NFS version 4 referrals

       RFC 5716 for FedFS requirements and overview

COLOPHON

       This page is part of the fedfs-utils package.  A description of	the  project  and  information	about  reporting  bugs	can  be  found	at
       http://wiki.linux-nfs.org/wiki/index.php/FedFsUtilsProject.

AUTHOR

       Chuck Lever <chuck.lever@oracle.com>

								  3 February 2014						    MOUNT.FEDFS(8)