mount_cachefs: mount, umount - mount and unmount CacheFS file systems
[specific_options] resource mount_point
The utility attaches a named resource to the file system hierarchy at
the pathname location mount_point, which must already exist. If
mount_point has any contents prior to the operation, the contents
remain hidden until the resource is once again unmounted. The CacheFS-
specific version of the command mounts a cached file system; if neces‐
sary, it NFS-mounts its back file system. It also provides a number of
options that are CacheFS-specific for controlling the caching process.
CacheFS can be used only with NFSv2 or NFSv3. It cannot be used with
NFSv4. If NFSv4 is enabled by default CacheFS mount fails, unless the
user specifies that vers is 2 or 3. See mount_nfs(1M) for the descrip‐
tion of vers.
The utility unmounts mounted file systems.
Only a superuser can mount and unmount file systems.
See mount_nfs(1M) for the description of resource.
See mount(1M) for the description of the options.
Set file system specific options according to a comma-separated
list with no intervening spaces. Notice that the backfstype argu‐
ment must be specified.
Specifies that cached attributes are held for no more than n sec‐
onds after directory update. After n seconds, all directory
information is purged from the cache. The default value is sec‐
Specifies that cached attributes are held
for at least n seconds after directory update. After n
seconds, CacheFS checks to see if the directory modifica‐
tion 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 seconds.
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 seconds.
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
Sets and to n.
The file system type of the back file system (for
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 name of the cache directory.
ID is a string specifying a particular instance of a cache.
If you do not specify a cache ID, CacheFS will construct
Verifies cache consistency only when explicitly
requested, rather than periodic checking that is done by
default. A consistency check is requested by using the
option of the command. This option is useful for back file
systems that change infrequently, for example, The and are
Causes the front file system to interpret the mode bits
used for access checking instead of having the back file
system verify access permissions. Do not use this argument
with secure NFS .
Disables cache consistency checking.
By default, periodic consistency checking is enabled.
Specify only when you know that the back file system will
not be modified. Trying to perform cache consistency check
using will result in error. The and are mutually exclu‐
Disable ACL functionality.
If you try to change ACL entries for a file on a CacheFS
file system mounted with the option an error is returned.
However, if you try to get the ACL entries for a file,
CacheFS will return fabricated ACL entries by using UNIX
file permissions. By default, the CacheFS file system sup‐
ports ACL functionality. See aclv(5) for a description of
Purge any cached information for the specified file
Remounts a read-only file system as read-write (using
the rw option).
If specified when mounting a CacheFS file system, a
binary will be read and populated in the cache the first
time it is loaded. Subsequent access to the binary will be
satisfied from the cache.
Read-write (default) or read-only.
Allow (default) or disallow set-uid execution.
Verifies the cache consistency with the NFS client's
copy of file attributes, and coordinates with bakfs (NFS)
for delayed flushing of modified pages to the server. The
delayed flushing of pages improves CacheFS response times.
The must not be used when multiple clients are modifying
the same file. The and options are mutually exclusive.
Write modes for CacheFS.
The 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
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.
Allow the file system to be mounted over an existing mount point,
making the underlying file system inaccessible. If a mount is
attempted on a pre-existing mount point without setting this flag,
the mount will fail, producing the error "device busy".
When processing an unknown
specific_option, the utility prints a warning message and pro‐
cesses the next one. This option prevents printing the warning
CacheFS-mount the file system which is already NFS-mounted on as
Lines similar to the following appear in the file after the command is
Mount a CacheFS filesystem over NFS Version 2.
was developed by Sun Microsystems, Inc.
SEE ALSOcfsadmin(1M), fsck_cachefs(1M), mount(1M).