NAME
     nsupdate - Update name servers interactively

SYNOPSIS
     nsupdate [ - d ] [ -v ] [filename]

     nsupdate

DESCRIPTION
     nsupdate updates the Internet domain name  servers.  It
     has two modes: interactive and non-interactive.  Interactive
     mode allows the user  to  update  servers  with  information
     about  various  hosts  and  domains. Non-interactive mode allows
     for batch updates of zones. Both modes assume that the nameserver
     allows updates (see allow-update option in configuring in.named) 
     from the host where nsupdate is being run. 

OPTIONS 
     -d is the debug mode.
     -v makes use of TCP instead of UDP

     filename  The name of the file containing the update requests and
               entries. Data in the file must contain one line per entry
               and should be of the form
                        class section name ttl type rdata
                Where:
                class can be any of the following opcodes
                update, zone, prereq

                section can be one of the following opcodes
                add, delete, nxdomain, yxdomain, nxrrset, yxrrset

                name is the name of the entry being added

                ttl  is the time to live (in seconds) for this entry, 
                following which the nameserver will no longer serve the
                entry

                type is the RR type. (a, cname, ns, mx, txt ..etc)

                rdate is the data appropriate for the RR type being 
                updated. 

USAGE
   Interactive Mode
        In the interactive mode, the user is expected to provide the
        update data in the
                class section name ttl type rdata
        format against each promot, with each field separated by a space.
        A return at with no data assumes the end of input and all update
        entries are the nameserver is updated in one atomic operation.

        A ^D ends the interactive mode and exits the program.

   Non-Interactive Mode
        In the non-interactive mode, the user is expected to provide the
        update data in a file. Data in the file is  in the form of rows 
        and columns. Each row must contain the following update data
                class section name ttl type rdata

EXAMPLE 
   Interactive Mode

Here is an exmple of an nsupdate session:

Example 1: This example updates the nads.zn zone with a cname entry for 
ivy18.nads.zn as www.nads.zn

% nsupdate
> update add www.nads.zn 60 in cname ivy18.nads.zn
> 
res_mkupdate: packet size = 49
;; res_send()
;; ->>HEADER<<- opcode: UPDATE, status: NOERROR, id: 53349
;; flags:; ZONE: 1, PREREQUISITE: 0, UPDATE: 1, ADDITIONAL: 0
;;      nads.zn, type = SOA, class = IN
www.nads.zn.            1M IN CNAME     ivy18.nads.zn.
;; Querying server (# 1) address = 192.168.1.1
;; got answer:
;; ->>HEADER<<- opcode: UPDATE, status: NOERROR, id: 53349
;; flags: qr ra; ZONE: 0, PREREQUISITE: 0, UPDATE: 0, ADDITIONAL: 0


2. The 2nd example deletes the entry created in example 1.
% nsupdate
> update delete www.nads.zn. cname
> 
;; res_mkquery(0, www.nads.zn, 1, 6)
;; res_send()
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 53350
;; flags: rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0
;;      www.nads.zn, type = SOA, class = IN
;; Querying server (# 1) address = 192.168.1.1
;; got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 53350
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 0
;;      www.nads.zn, type = SOA, class = IN
www.nads.zn.            1M IN CNAME     ivy18.nads.zn.
nads.zn.                1D IN SOA       nserver.eng.nads.com.  admin.myhost.eng.n ads.com. (
                                        1998012604      ; serial
                                        3H              ; refresh
                                        1H              ; retry
                                        1W              ; expiry
                                        1D )            ; minimum
 
;; res_mkquery(0, nads.zn, 1, 6)
;; res_send()
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 53351
;; flags: rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0
;;      nads.zn, type = SOA, class = IN
;; Querying server (# 1) address = 192.168.1.1
;; got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 53351
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1
;;      nads.zn, type = SOA, class = IN
nads.zn.                1D IN SOA       nserver.eng.nads.com.  admin.myhost.eng.n ads.com. (
                                        1998012604      ; serial
                                        3H              ; refresh
                                        1H              ; retry
                                        1W              ; expiry
                                        1D )            ; minimum

nads.zn.                1D IN NS        obelix.nads.zn.
obelix.nads.zn.         1D IN A         192.168.1.1
res_mkupdate: packet size = 41
;; res_send()
;; ->>HEADER<<- opcode: UPDATE, status: NOERROR, id: 53352
;; flags:; ZONE: 1, PREREQUISITE: 0, UPDATE: 1, ADDITIONAL: 0
;;      nads.zn, type = SOA, class = IN
;; Querying server (# 1) address = 192.168.1.1
;; got answer:
;; ->>HEADER<<- opcode: UPDATE, status: NOERROR, id: 53352
;; flags: qr ra; ZONE: 0, PREREQUISITE: 0, UPDATE: 0, ADDITIONAL: 0


   Non-Interactive Mode
        $nsupdate nsupd.txt
        where nsupd.txt contains the following information
                update delete www.nads.zn.
                update add www.nads.zn. 60 CNAME ivy18.nads.zn

Courtesy Ravindra R. Iyer, Sun Microsystems.