-.P
-However, administrators can choose to add and delete individual file systems
-without modifying
-.B /etc/exports
-using
-.BR exportfs .
-.P
-Any export requests which identify a specific host (rather than a
-subnet or netgroup etc) are entered directly into the kernel's export
-table as well as being written to
-.BR /var/lib/nfs/xtab .
-Further, any mount points listed in
-.B /var/lib/nfs/rmtab
+However, a system administrator can choose to add or delete
+exports without modifying
+.I /etc/exports
+or files under
+.I /etc/exports.d
+by using the
+.B exportfs
+command.
+.PP
+.B exportfs
+and its partner program
+.B rpc.mountd
+work in one of two modes: a legacy mode which applies to 2.4 and
+earlier versions of the Linux kernel, and a new mode which applies to
+2.6 and later versions, providing the
+.B nfsd
+virtual filesystem has been mounted at
+.I /proc/fs/nfsd
+or
+.IR /proc/fs/nfs .
+On 2.6 kernels, if this filesystem is not mounted, the legacy mode is used.
+.PP
+In the new mode,
+.B exportfs
+does not give any information to the kernel, but provides it only to
+.B rpc.mountd
+through the
+.I /var/lib/nfs/etab
+file.
+.B rpc.mountd
+then manages kernel requests for information about exports, as needed.
+.PP
+In the legacy mode,
+exports which identify a specific host, rather than a subnet or netgroup,
+are entered directly into the kernel's export table,
+as well as being written to
+.IR /var/lib/nfs/etab .
+Further, exports listed in
+.I /var/lib/nfs/rmtab