-a |
Exports all directories listed in the exports file. |
-v |
Prints the name of each directory as it is exported or unexported. |
-u |
Unexports the directories you specify. When used with the -a flag,
unexports all exported directories. When used with both the -a and -f flags,
unexports all directories in the specified export file. |
-i |
Allows the exporting of directories not specified in the exports
file or ignores the options in the exports file. Unless the -f flag
is used to specify an alternate file, the exportfs command
will normally consult the /etc/exports file for the options
associated with the exported directory." |
-f File |
Specifies an export file, instead of the /etc/exports file,
that contains a list of directories that you can export. This file
should follow the same format as the /etc/exports file. NOTE:
This alternate file will not be used for exporting directories automatically
when the system and NFS is started. The /etc/exports file is
the only file that is supported for specifying directories to export
at system start. |
-F |
Specifies that a forced unexport should be
performed. Use this flag only with the -u flag. This flag has
no effect when unexporting a V2/V3 export. A V4 unexport can fail
due to associated state. This flag forces the release of any state
associated with a V4 export. |
-oOptions |
Specifies the optional characteristics for the directory being
exported. You can enter more than one variable by separating them
with commas. For options taking a Client parameter, Client can
specify a hostname, a dotted IP address, a network name, or a subnet
designator. A subnet designator is of the form "@host/mask",
where host is either a hostname or a dotted IP address and mask specifies
the number of bits to use when checking access. If mask is
not specified, a full mask is used. For example, the designator @client.group.company.com/16 will
match all Clients on the company.com subnet. A designator
of @client.group.company.com/24 will match only the
Clients on the group.company.com subnet. Choose
from the following options: - ro
- Exports the directory with read-only permission. If not specified,
the directory is exported with read-write permission.
- ro=Client[:Client]
- Exports the directory with read-only permission to the specified
Clients. Exports the directory with read-write permissions to Clients
not specified in the list. A read-only list cannot be specified if
a read-write list has been specified.
- rw
- Exports the directory with read-write permission to all Clients.
- rw=Client [:Client]
- Exports the directory with read-write permission to the specified
Clients. Exports the directory read-only to Clients not in the list.
A read-write list cannot be specified if a read-only list has been
specified.
- anon =UID
- Uses the UID value as the effective user ID, if a request
comes from a root user.
The default value for this option is
-2. In NFS version 2 and NFS version 3, setting the value of the anon option
to -1 disables anonymous access. Thus, by default, secure NFS accepts
nonsecure requests as anonymous, and users who want more security
can disable this feature by setting anon to a value of -1.
- root=Client[:Client]
- Allows root access from the specified clients in the list. Putting
a host in the root list does not override the semantics of the other
options. For example, this option denies the mount access from a host
present in the root list but absent in the access list.
- access=Client[:Client,...]
- Gives mount access to each client listed. A client can be either
a host name or a net group name. Each client in the list is first
checked for in the /etc/netgroup database and then in the /etc/hosts database.
The default value allows any machine to mount the given directory.
- secure
- Requires clients to use a more secure protocol when accessing
the directory.
|
-o Options (continued) |
- sec=flavor[:flavor...]
-
This option is used to specify a list of security methods
that may be used to access files under the exported directory. Most
exportfs options can be clustered using the sec option.
Options following a sec option are presumed
to belong with the preceding sec option.
Any number of sec stanzas may be specified,
but each security method can be specified only once. Within each sec stanza
the ro, rw, root,
and access options may be specified once.
Only the public, anon and vers options
are considered global for the export. If the sec option
is used to specify any security method, it must be used to specify
all security methods. In the absence of any sec option,
all authentication flavors are allowed.
Allowable flavor
values are: - sys
- UNIX authentication.
This is the default method.
- dh
- DES authentication.
- none
- Allow mount requests to proceed with anonymous credentials if
the mount request uses an authentication flavor not specified in the
export.
- krb5
- Kerberos. Authentication only.
- krb5i
- Kerberos. Authentication and integrity.
- krb5p
- Kerberos. Authentication, integrity, and privacy.
The secure option may be
specified, but not in conjunction with a sec option.
The secure option is deprecated and may
be eliminated. Use sec=dh instead.
- vers=version_number[:version_number...]
- Specifies which versions of NFS are allowed to access the exported
directory. Valid versions are 2, 3, and 4. Versions 2 and 3 cannot
be selected exclusively. Specifying either version 2 or version 3
will allow access by both NFS version 2 and NFS version 3. Version
4 can be selected exclusively. The default is to allow access
using NFS protocol versions 2 and 3.
- exname=external-name
- Exports the directory by the specified external name. The external
name must begin with the nfsroot name.
See the description of the /etc/exports file
for a description of the nfsroot name.
This option applies only to directories exported for access by NFS
version 4 protocol.
- deleg={yes | no}
- Enables or disables file delegation for the specified export.
This option overrides the system-wide delegation enablement for this
export. The system-wide enablement is done through nfso.
|
-o Options (continued) |
- refer=rootpath@host[+host][:rootpath@host[+host]]
- A namespace referral will be created at the specified path. The
referral directs clients to the specified alternate locations where
they can continue operations. A referral is a special object. If a
nonreferral object exists at the specified path, the export is disallowed
and an error message is printed. If nothing exists at the specified
path, a referral object is created there that includes the path name
directories leading to the object. Multiple referrals can be created
within a file system. A referral cannot be specified for the nfsroot.
The name localhost cannot be used as a hostname.
This refer option is allowed only for version
4 exports. If the export specification allows version 2 or version
3 access, an error message will be printed and the export will be
disallowed. Unexporting the referral object has the effect of removing
the referral locations information from the referral object. The object
itself is not removed by unexporting. Use rm if
you want to remove the object. The administrator must ensure that
appropriate data is available at the referral servers. This option
is available only on AIX 5L™ Version 5.3 with the 5300-03 Recommended Maintenance package or
later.
Note: A referral export can only be made if replication is
enabled on the server. Use chnfs -R on to
enable replication.
|
-o Options (continued) |
- replicas=rootpath@host[+host][:rootpath@host[+host]]
- Replica location information will be associated with the export
path. The replica information can be used by NFS version 4 clients
to redirect operations to the specified alternate locations if the
current server becomes unavailable. The administrator should ensure
that appropriate data is available at the replica servers. Because
replica information applies to an entire file system, the specified
path must be the root of a file system. If the path is not a file
system root, the export is disallowed and an error message is printed.
The name localhost cannot be used as a hostname.
This replicas option is meaningful only
for version 4 exports. If the option is used on an export that allows
version 2 or version 3 access, the operation is allowed, but the
replica information is ignored by the version 2 and version 3 servers.
If the directory being exported is not in the replica list, the entry exported
directory@current host will
be added as the first replica location. This option is available only
on AIX® 5.3 with 5300-03 or later.
A replica export can only be made if replication is enabled on the
server. By default, replication is not enabled. If replica exports
will be made at system boot, replication should be enabled by using
the chnfs -R on command. Replica locations
can also be specified for the nfsroot. This
can be done only using chnfs -R host[+host].
If the current host is not specified in the list, it will be added
as the first replica host. The rootpath is
not needed or allowed in this case because nfsroot is
replicated only to the nfsroots of the specified
hosts. The chnfs program can be used to
enable or disable replication. Changing the replication mode can only
be done if no NFS version 4 exports are active. If the server's replication
mode is changed, file handles issued by the server during the previous
replication mode will not be honored by the server. This can cause
application errors on clients holding old file handles. Be careful
when changing the replication mode of the server. If possible, all
clients who have mounts to the server should unmount them before the
server's replication mode is changed. The replica location information
associated with the directory can be changed by modifying the replica
list and reexporting the directory. The new replica information replaces
the old replica information. NFS clients are expected to refresh replica
information on a regular basis. If the server changes the replica
information for an export, it might take time for the client to notice.
This is not much of a problem if new replica locations are added,
because clients holding the old information still have correct, if
incomplete, replica information. Removing replica information can
be problematic because it can result in clients holding incorrect
replica information for a period of time. To aid clients in detecting
the new information, exportfs will attempt
to touch the replicated directory. This changes the timestamps on
the directory, which in turn causes the client to refetch the directory's
attributes. This operation might not be possible, however, if the
replicated file system is read-only. When changing replica information
for a directory, be aware that there could be some latency between
changing the information and clients noticing the new information.
|
-o Options (continued) |
- noauto
- Accepts the replicas specification as-is. Does not automatically
insert the primary hostname as one of the replica locations if it
has not been specified.
- scatter
- Defines how the alternate locations list is generated from the
servers specified on the refer or replicas option. If
the noauto option is not used, the alternate locations list
also includes the primary host name as one of the replica locations.
The scatter option applies only to directories exported for
access by NFS version 4 protocol. The scatter option has three
allowable values:
- full
- All of the servers are scattered to form the combinations of alternate
locations.
- partial
- The first location of all the combinations is fixed to the first
server specified on the refer or replicas option. The
rest of the locations and the first location are scattered as if they
are scattered using the scatter=full method.
- none
- No scatter is to be used. The value can also be used to disable
scattering if enabled previously.
Whenever the attributes of a Client change, all
export entries that contain that Client as a parameter should be exported
again. Events that can change a Client's attributes include modifying
a netgroup or changing the IP address of a client. Failure to do so
can result in the server using old client information.
|
-V Exported Version |
Specifies the version number. Valid version numbers are 2,
3 and 4. |