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(am-utils.info)Caching Filesystem

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Caching Filesystem (`cachefs')
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   The "cachefs" (`type:=cachefs') filesystem caches files from one
location onto another, presumably providing faster access.  It is
particularly useful to cache from a larger and remote (slower) NFS
partition to a smaller and local (faster) UFS directory.

The following options must be specified:

`cachedir'
     the directory where the cache is stored.

`rfs'
     the path name to the "back file system" to be cached from.

`fs'
     the "front file system" mount point to the cached files, where Amd
     will set a symbolic link pointing to.

   A CacheFS entry for, say, the `/import' Amd mount point, might be:

     copt  type:=cachefs;cachedir:=/cache;rfs:=/import/opt;fs:=/n/import/copt

   Access to the pathname `/import/copt' will follow a symbolic link to
`/n/import/copt'.  The latter is the mount point for a caching file
system, that caches from `/import/opt' to `/cache'.

   Caveats:
  1. This file system is currently only implemented for Solaris 2.x!

  2. Before being used for the first time, the cache directory must be
     initialized with `cfsadmin -c CACHEDIR'.  See the manual page for
     cfsadmin(1M) for more information.

  3. The "back file system" mounted must be a complete file system, not
     a subdirectory thereof; otherwise you will get an error "Invalid
     Argument".

  4. If Amd aborts abnormally, the state of the cache may be
     inconsistent, requiring running the command `fsck -F cachefs
     CACHEDIR'.  Otherwise you will get the error "No Space Left on
     Device".