ipconfig: document DHCP hostname and DNS record

Now it's possible to update the DNS record for $HOST_NAME with

	ip=::::$HOST_NAME::dhcp

CC: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/Documentation/filesystems/nfs/nfsroot.txt b/Documentation/filesystems/nfs/nfsroot.txt
index 3ba0b945aaf8..f2430a7974e1 100644
--- a/Documentation/filesystems/nfs/nfsroot.txt
+++ b/Documentation/filesystems/nfs/nfsroot.txt
@@ -124,6 +124,8 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
 
   <hostname>    Name of the client. May be supplied by autoconfiguration,
                 but its absence will not trigger autoconfiguration.
+                If specified and DHCP is used, the user provided hostname will
+                be carried in the DHCP request to hopefully update DNS record.
 
                 Default: Client IP address is used in ASCII notation.