Merge branch 'upstream'

[nfs-utils.git] / utils / exportfs / exports.man

diff --git a/utils/exportfs/exports.man b/utils/exportfs/exports.man
index 7ab7640da1350b8f8b6733c007135fb13d639abe..fd6d4be4a74bfe53a44799eef5fcabc7399e2fa1 100644 (file)
--- a/utils/exportfs/exports.man
+++ b/utils/exportfs/exports.man
@@ -1,5 +1,4 @@
-.TH EXPORTS 5 "28 October 1999"
-.UC 5
+.TH EXPORTS 5 "4 March 2005" "Linux" "Linux File Formats Manual"

 .SH NAME
 exports \- NFS file systems being exported (for Kernel based NFS)
 .SH SYNOPSIS
 .SH NAME
 exports \- NFS file systems being exported (for Kernel based NFS)
 .SH SYNOPSIS


@@ -30,6 +29,9 @@ double quotes. You can also specify spaces or other unusual character in
 the export name using a backslash followed by the character code as three
 octal digits.
 .PP
 the export name using a backslash followed by the character code as three
 octal digits.
 .PP

+To apply changes to this file, run exportfs -ra or (on Debian)
+/etc/init.d/nfs-kernel-server reload.
+.PP

 .SS Machine Name Formats
 NFS clients may be specified in a number of ways:
 .IP "single host
 .SS Machine Name Formats
 NFS clients may be specified in a number of ways:
 .IP "single host


@@ -79,6 +81,11 @@ may work by accident when reverse DNS lookups fail.
 '''.B \-\-public\-root
 '''option. Multiple specifications of a public root will be ignored.
 .PP
 '''.B \-\-public\-root
 '''option. Multiple specifications of a public root will be ignored.
 .PP

+.SS RPCSEC_GSS security
+To restrict access to an export using rpcsec_gss security, use the special
+string "gss/krb5" as the client.  It is not possible to simultaneously require
+rpcsec_gss and to make requirements on the IP address of the client.
+.PP

 .SS General Options
 .IR exportfs
 understands the following export options:
 .SS General Options
 .IR exportfs
 understands the following export options:


@@ -105,6 +112,13 @@ Using this option usually improves performance, but at the cost that
 an unclean server restart (i.e. a crash) can cause data to be lost or
 corrupted.
 
 an unclean server restart (i.e. a crash) can cause data to be lost or
 corrupted.
 

+.TP
+.IR sync
+Reply to requests only after the changes have been committed to stable
+storage (see
+.IR async
+above).
+

 In releases of nfs-utils upto and including 1.0.0, this option was the
 default.  In this and future releases,
 .I sync
 In releases of nfs-utils upto and including 1.0.0, this option was the
 default.  In this and future releases,
 .I sync


@@ -164,9 +178,17 @@ copes with the situation effectively.
 The option can be explicitly disabled with
 .IR hide .
 .TP
 The option can be explicitly disabled with
 .IR hide .
 .TP

+.IR crossmnt
+This option is similar to
+.I nohide
+but it makes it possible for clients to move from the filesystem marked
+with crossmnt to exported filesystems mounted on it.  Thus when a child
+filesystem "B" is mounted on a parent "A", setting crossmnt on "A" has
+the same effect as setting "nohide" on B.
+.TP

 .IR no_subtree_check
 This option disables subtree checking, which has mild security
 .IR no_subtree_check
 This option disables subtree checking, which has mild security

-implications, but can improve reliability is some circumstances.
+implications, but can improve reliability in some circumstances.

 
 If a subdirectory of a filesystem is exported, but the whole
 filesystem isn't then whenever a NFS request arrives, the server must
 
 If a subdirectory of a filesystem is exported, but the whole
 filesystem isn't then whenever a NFS request arrives, the server must


@@ -185,7 +207,7 @@ subtree checking is also used to make sure that files inside
 directories to which only root has access can only be accessed if the
 filesystem is exported with
 .I no_root_squash
 directories to which only root has access can only be accessed if the
 filesystem is exported with
 .I no_root_squash

-(see below), even the file itself allows more general access.
+(see below), even if the file itself allows more general access.

 
 As a general guide, a home directory filesystem, which is normally
 exported at the root and may see lots of file renames, should be
 
 As a general guide, a home directory filesystem, which is normally
 exported at the root and may see lots of file renames, should be


@@ -218,6 +240,21 @@ be explicitly requested with either of the synonymous
 .IR auth_nlm ,
 or
 .IR secure_locks .
 .IR auth_nlm ,
 or
 .IR secure_locks .

+.TP
+.IR no_acl
+On some specially patched kernels, and when exporting filesystems that
+support ACLs, this option tells nfsd not to reveal ACLs to clients, so
+they will see only a subset of actual permissions on the given file
+system.  This option is safe for filesystems used by NFSv2 clients and
+old NFSv3 clients that perform access decisions locally.  Current
+NFSv3 clients use the ACCESS RPC to perform all access decisions on
+the server.  Note that the
+.I no_acl
+option only has effect on kernels specially patched to support it, and
+when exporting filesystems with ACL support.  The default is to export
+with ACL support (i.e. by default,
+.I no_acl
+is off).

 
 '''.TP
 '''.I noaccess
 
 '''.TP
 '''.I noaccess


@@ -237,6 +274,47 @@ or
 '''.TP
 '''.IR link_absolute
 '''Leave all symbolic link as they are. This is the default operation.
 '''.TP
 '''.IR link_absolute
 '''Leave all symbolic link as they are. This is the default operation.

+
+.TP
+.IR mountpoint= path
+.TP
+.I mp
+This option makes it possible to only export a directory if it has
+successfully been mounted.
+If no path is given (e.g.
+.IR mountpoint " or " mp )
+then the export point must also be a mount point.  If it isn't then
+the export point is not exported.  This allows you to be sure that the
+directory underneath a mountpoint will never be exported by accident
+if, for example, the filesystem failed to mount due to a disc error.
+
+If a path is given (e.g.
+.IR mountpoint= "/path or " mp= /path)
+then the nominted path must be a mountpoint for the exportpoint to be
+exported.
+
+.TP
+.IR fsid= num
+This option forces the filesystem identification portion of the file
+handle and file attributes used on the wire to be
+.I num
+instead of a number derived from the major and minor number of the
+block device on which the filesystem is mounted.  Any 32 bit number
+can be used, but it must be unique amongst all the exported filesystems.
+
+This can be useful for NFS failover, to ensure that both servers of
+the failover pair use the same NFS file handles for the shared filesystem
+thus avoiding stale file handles after failover.
+
+Some Linux filesystems are not mounted on a block device; exporting
+these via NFS requires the use of the
+.I fsid
+option (although that may still not be enough).
+
+The value  0 has a special meaning when use with NFSv4.  NFSv4 has a
+concept of a root of the overall exported filesystem. The export point
+exported with fsid=0 will be used as this root.
+

 .SS User ID Mapping
 .PP
 .I nfsd
 .SS User ID Mapping
 .PP
 .I nfsd


@@ -263,7 +341,7 @@ By default,
 '''in the password file at startup time. If it isn't found, a uid and gid
 .I exportfs
 chooses a uid and gid
 '''in the password file at startup time. If it isn't found, a uid and gid
 .I exportfs
 chooses a uid and gid

-of -2 (i.e. 65534) for squashed access. These values can also be overridden by
+of 65534 for squashed access. These values can also be overridden by

 the
 .IR anonuid " and " anongid
 options.
 the
 .IR anonuid " and " anongid
 options.


@@ -441,6 +519,12 @@ don't use a reserved port for NFS.
 '''entry.
 .SH FILES
 /etc/exports
 '''entry.
 .SH FILES
 /etc/exports

+.SH SEE ALSO
+.BR exportfs (8),
+.BR netgroup (5),
+.BR mountd (8),
+.BR nfsd (8),
+.BR showmount (8).

 '''.SH DIAGNOSTICS
 '''An error parsing the file is reported using syslogd(8) as level NOTICE from
 '''a DAEMON whenever nfsd(8) or mountd(8) is started up.  Any unknown
 '''.SH DIAGNOSTICS
 '''An error parsing the file is reported using syslogd(8) as level NOTICE from
 '''a DAEMON whenever nfsd(8) or mountd(8) is started up.  Any unknown