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 mount_cachefs(1M)					   mount_cachefs(1M)




 NAME
      mount_cachefs - mount CacheFS file systems

 SYNOPSIS
      mount -F cachefs [ generic_options ] -o backfstype=file_system_type
	   [ other_cacheFS_options ] special_mount_point

 DESCRIPTION
      The CacheFS-specific version of the mount command mounts a cached file
      system; if necessary, it NFS-mounts its back file system.	 It also
      provides a number of CacheFS-specific options for controlling the
      caching process.

    Options
      To mount a CacheFS file system, use the generic mount command with the
      -F option followed by the argument cachefs.  The following generic
      mount options are available:

      -m	     Mount the file system without making an entry in the
		     /etc/mnttab file.

      -O	     Overlay mount.  Allows the filesystem to be mounted
		     over an existing mount point, making the underlying
		     filesystem inaccessible.  If a mount is attempted on a
		     pre-existing mount point without setting this flag,
		     mount will fail with the error:

		     mount -F cachefs: mount failed Device busy.

      -r	     Mount the file system read-only.

      The following arguments to the -o option are specifically for CacheFS
      mounts.  Use commas to separate multiple options. Note: the backfstype
      argument must be specified.

      backfstype=file_system_type
		     The file system type of the back file system (for
		     example, nfs).

      backpath=path  Specifies where the back file system is already
		     mounted. If this argument is not supplied, CacheFS
		     determines a mount point for the back file system.	 The
		     back file system must be read-only.

      cachedir=directory
		     The name of the cache directory.

      cacheid=ID     ID is a string specifying a particular instance of a
		     cache.  If you do not specify a cache ID, CacheFS will
		     construct one.




 Hewlett-Packard Company	    - 1 -   HP-UX Release 11i: November 2000






 mount_cachefs(1M)					   mount_cachefs(1M)




      write-around | non-shared
		     Write modes for CacheFS.  The write-around mode (the
		     default) handles writes the same as NFS does; that is,
		     writes are made to the back file system, and the
		     affected file is purged from the cache.  You can use
		     the non-shared mode when you are sure that no one else
		     will be writing to the cached file system. In this
		     mode, all writes are made to both the front and the
		     back file system, and the file remains in the cache.

      noconst	     Disables cache consistency checking. By default,
		     periodic consistency checking is enabled. Specify
		     noconst only when you know that the back file system
		     will not be modified. Trying to perform cache
		     consistency check using cfsadmin -s will result in
		     error.  demandconst and noconst are mutually exclusive.

      demandconst    Verifies cache consistency only when explicitly
		     requested, rather than the periodic checking that is
		     done by default.  A consistency check is requested by
		     using the -s option of the cfsadmin(1M) command.  This
		     option is useful for back file systems that change
		     infrequently, for example, /usr/bin.  demandconst and
		     noconst are mutually exclusive.

      local-access   Causes the front file system to interpret the mode bits
		     used for access checking instead or having the back
		     file system verify access permissions. Do not use this
		     argument with secure NFS .

      purge	     Purge any cached information for the specified file
		     system.

      rw | ro	     Read-write (default) or read-only.

      suid | nosuid  Allow (default) or disallow set-uid execution.

      acregmin=n     Specifies that cached attributes are held for at least
		     n seconds after file modification.	 After n seconds,
		     CacheFS checks to see if the file modification time on
		     the back file system has changed.	If it has, all
		     information about the file is purged from the cache and
		     new data is retrieved from the back file system.  The
		     default value is 30 seconds.

      acregmax=n     Specifies that cached attributes are held for no more
		     than n seconds after file modification.  After n
		     seconds, all file information is purged from the cache.
		     The default value is 30 seconds.





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 mount_cachefs(1M)					   mount_cachefs(1M)




      acdirmin=n     Specifies that cached attributes are held for at least
		     n seconds after directory update.	After n seconds,
		     CacheFS checks to see if the directory modification
		     time on the back file system has changed.	If it has,
		     all information about the directory is purged from the
		     cache and new data is retrieved from the back file
		     system.  The default value is 30 seconds.

      acdirmax=n     Specifies that cached attributes are held for no more
		     than n seconds after directory update.  After n
		     seconds, all directory information is purged from the
		     cache.  The default value is 30 seconds.

      actimeo=n	     Sets acregmin, acregmax, acdirmin, and acdirmax to n.

 EXAMPLES
      The following example CacheFS-mounts the file system server1:/user2,
      which is already NFS-mounted on /usr/abc as /xyz.

	   example# mount -F cachefs -o backfstype=nfs,backpath=/usr/abc,
	       cachedir=/cache1 server1:/user2 /xyz

      The lines similar to the following appear in the /etc/mnttab file
      after the mount command is executed:

	   server1:/user2      /usr/abc	       nfs
	   /usr/abc	       /cache1/xyz     cachefs	  backfstype=nfs

 AUTHOR
      mount_cachefs was developed by Sun Microsystems, Inc.

 SEE ALSO
      cfsadmin(1M), fsck_cachefs(1M), mount(1M).





















 Hewlett-Packard Company	    - 3 -   HP-UX Release 11i: November 2000