share(1Mnfs)
share --
make local NFS resource available for mounting by remote systems
Synopsis
share -F nfs [-o specific_options] [-d description] pathname [resource]
Description
The NFS®-specific share command makes local resources
available for mounting by remote systems.
Options
The following options are available to the share command:
-F-
Specifies the File System Type (FSType). This option may be omitted if NFS
is the first filesystem type listed in the /etc/dfs/fstypes file.
-o specific_options-
Specify options in a comma-separated list of keywords and
attribute-value-assertions for interpretation by the
file-system-type-specific command.
The specific_options can be any combination of the following:
anon=uid-
Set uid to be the effective user ID of unauthenticated
users if AUTH_DES authentication is used, or to be root if
AUTH_UNIX authentication is used. By default, unknown users are
given the effective user ID UID_NOBODY. If uid
is set to -1, access is denied.
asyncwrites-
All writes to the shared filesystem will be asynchronous. This may
improve write performance on the server, but carries with it the
risk of data loss on server crashes.
index=index_path-
On a web server that supports WebNFS,
serve an index file if a remote user browses a directory rather than a
file. The specified index_path is appended to
the pathname to form the pathname of the index file. If
the index option is not used to specify an index_path,
the pathname formed from pathname/index.html is used.
public-
On a web server, the directory specified by pathname
is to be shared as the publicly-accessible WebNFS directory.
ro-
Sharing will be read-only to all clients.
ro=client[:client] ...-
Sharing will be read-only to the listed clients; overrides the
rw suboption for the clients specified.
root=host[:host] ...-
Only root users from the specified hosts will have root access. By default,
no host has root access.
rw-
Sharing will be read-write to all clients.
rw=client[:client] ...-
Sharing will be read-write to the listed clients; overrides the
ro suboption for the clients specified.
secure-
Clients must use the AUTH_DES authentication of RPC.
AUTH_UNIX authentication is the default.
If no specific_options are specified, then by default sharing
will be read-write to all clients.
-d description-
Provides a comment that describes the resource to be shared.
pathname-
Specifies the pathname of the resource to be shared.
resource-
Specifies the name of the resource to be shared.
Files
/etc/dfs/fstypes-
/etc/dfs/sharetab-
Usage
If no argument is specified, then share displays all of the
NFS resources currently shared.
NOTE:
The specific_options ro=, rw=, and
root= are guaranteed to work over UDP and TCP
but may not work over other transport providers.
In addition, if a resource is shared with a ro= list and a
root= list, any host that is on the root= list will be
given read-only access, regardless of whether that host is specified in
the ro= list, unless rw is declared as the default,
or the host is mentioned in a rw= list. The same is true if the
resource is shared with ro as the default.
Multiple clients may be specified using the format:
``IPaddr/mask_length''
instead of naming them individually.
IPaddr is an IP address,
and mask_length is the number of leading 1's in a bitmask that will
be applied to both IPaddr and the requesting client's
IP address before comparing the resulting values. A match is
obtained if the computed values are equal.
For example, a client specified as ``192.168.12.0/24''
includes all hosts whose IP address begins ``192.168.12'' when
OR'ed with the mask ``255.255.255.0''.
NOTE:
The result of ORing IPaddr with the inverse
of the specified mask must be zero. Otherwise, share will judge the
address invalid. A client specified as
``192.168.12.0/16'' would thus not be allowed.
share advertises its resources on applicable transports specified
by the NETPATH environment variable if the variable is not
set to NULL. Otherwise, share scans
the /etc/netconfig file to find all appropriate transports.
The recommended use of the NETPATH variable with the
share command is as follows:
# NETPATH=udp share -F nfs ...
Specifying NETPATH in this manner affects only the execution of
the share command and does not affect the shell environment.
Exit codes
0-
Successful exit
33-
Usage error
34-
Could not add to sharetab
35-
Could not delete from sharetab
36-
Could not share
37-
Error in options parsing
Warnings
The share command will fail if both ro and
rw (with no qualifiers) are specified. If the same client name
exists in both the ro= and rw= lists, the rw
will override the ro, giving read/write access to the client
specified.
Granting root access to other hosts has far reaching security implications;
use the root= option with extreme caution.
Examples
Give read-only permissions to hostb:
share -F nfs -oro=hosta,root=hostb /var
share -F nfs -oro,root=hostb /var
Give read/write permissions to hostb:
share -F nfs -oro=hosta,rw=hostb,root=hostb /var
share -F nfs -oroot=hostb /var
Give read/write permissions to all hosts on network 192.168.16/24 but only
allow read-only access for hosts on networks 192.168.20/24 and
192.168.25/16:
share -F nfs -orw=192.168.16.0/24,ro=192.168.20.0/24:192.168.25.0/16 /var
References
share(1M),
unshare(1M),
unshare(1Mnfs)
© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 25 April 2004