exportfs(8) CLIX exportfs(8)
NAME
exportfs - Exports/unexports directories to NFS clients
SYNOPSIS
/etc/exportfs [-avu] [directory]
/etc/exportfs [-i] [-o options] [directory]
FLAGS
-a Exports all directories listed in /etc/exports, or if -u is
specified, unexports all of the currently exported
directories.
-v Displays each directory name as it is exported or unexported.
-u Unexports the specified directories.
-i Ignores the options in /etc/exports. By default, exportfs
consults /etc/exports for the options associated with the
exported directory.
-o options Specifies a comma-separated list of optional characteristics
for the directory being exported. The following options are
available:
ro Exports the directory as read-only. By default, the
directory is exported as read-write.
rw=hostname[:hostname] ...
Exports the directory as read-mostly. Read-mostly
means directories are exported as read-only to all
hosts not specified by hostname. By default, the
directory is exported as read-write to all hosts. The
limit for the number of hosts specified is 64.
root=hostname[:hostname] ...
Gives root access only to the root users from a
specified hostname. The default value grants root
access to no hosts. The limit for the number of hosts
specified is 64.
anon=uid
If a request comes from a ``root'' user, uses uid as
the effective user ID. Root users (uid 0) are always
considered unknown by the NFS server, unless they are
included in the root= option. The default value for
this option is -2. Setting the value of anon to -1
disables anonymous access, thus enhancing security.
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exportfs(8) CLIX exportfs(8)
By default, secure NFS accepts insecure requests as
anonymous.
access=client[:client] ...
Gives mount access to each client listed. A client
can be either a hostname or a netgroup. (See the
netgroup(4) command). The NIS netgroup map and the
/etc/hosts databases are searched for each client in
the list. The default access value allows any host to
mount the given directory. The access list size is
typically limited to 512 names but may vary depending
on the machine type.
auth Performs access authorization on the specified
directory for each NFS request. Only clients in the
access, root, or rw list will be able to access this
directory once it is exported with the auth option. If
a directory that was previously exported unrestricted
is re-exported with this option, clients with prior
mounts who are not in the new permission lists will be
denied access.
DESCRIPTION
The exportfs command makes a local directory (or file) available for
mounting over the network by NFS clients.
By default exportfs is invoked at boot time by the /etc/nfs script, and
uses information contained in the /etc/exports file to export directory
(which must be specified as a full pathname). The superuser can run
exportfs at any time to alter the list or characteristics of exported
directories. Directories currently exported are listed in the /etc/xtab
file.
With no options or arguments, exportfs displays the list of directories
currently exported.
The exportfs command consults the /etc/rmtab file for clients that are
netgroup members when exporting a directory. Since netgroup members are
dynamically added to the access list, it is necessary to replace these
entries when re-exporting occurs.
EXAMPLES
1. To export all directories listed in the /etc/exports file, displaying
each directory name as it is exported, enter:
exportfs -av
2. To unexport the directory /usr3, enter:
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exportfs(8) CLIX exportfs(8)
exportfs -u /usr3
3. To export the directory /usr3 with root access given to root users on
systems host1 and host2, ignoring information specified in
/etc/exports, enter:
exportfs -i -o root=host1:host2 /usr3
4. To display a list of all exported directories, enter:
exportfs
FILES
/etc/exports
Static export information.
/etc/xtab
Current state of exported directories.
/etc/netgroup
List of network groups.
/etc/rmtab
List of clients currently mounted.
CAUTIONS
You cannot export a directory that is a parent directory or subdirectory
of, and within the same file system, as a currently exported directory.
For example, you cannot export both /usr and /usr/ip32 if both directories
resided on the same disk partition.
If netgroup names are present in the access list, and expanding the
netgroups would cause the total number of hosts with access permission to
exceed the configured maximum, then it is possible that clients that are
netgroup members will be denied access.
There is a small performance penalty for the added overhead of exporting a
resource with the auth flag. This level of security is not required for
normal operation.
DIAGNOSTICS
Diagnostic messages are self-explanatory.
EXIT VALUES
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exportfs(8) CLIX exportfs(8)
The exportfs command exits with a value of 0 if successful. If
unsuccessful, it exits with a value of 1.
RELATED INFORMATION
Files: exports(4), netgroup(4), rmtab(4)
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