How to use an input file for nsupdate

The example below shows how to have nsupdate read subcommands from a file for BIND 9.

Create a z/OS UNIX file containing the following nsupdate subcommands. Assume the file is named nsupdate.commands.

            update delete oldhost.example.com A
            update add newhost.example.com 86400 A 172.16.1.1
            show
            send
            quit

Then issue the following command from the directory where the file, nsupdate.commands resides.
```
nsupdate nsupdate.commands
```
Because the zone and server subcommands were not explicitly issued, the defaults will come from the resolver configuration data set. Assume the following information is coded in the resolver configuration data set.
```
            domain     example.com
            nameserver 127.0.0.1
```
The name server on the local host would be used to look up the location of the example.com domain. Once the authoritative name server is located, the updates in the nsupdate.commands file are executed and sent to that name server.

The output is sent to stdout. The following information might appear on the z/OS UNIX screen.

> nsupdate nsupdate.commands
  Running nsupdate version 9
  Allocated socket 6, type udp
  Outgoing update query:
  ;; ->>HEADER<<- opcode: UPDATE, status: NOERROR, id:      0
  ;; flags: ; ZONE: 0, PREREQ: 0, UPDATE: 0, ADDITIONAL: 0
  ;; UPDATE SECTION:
  oldhost.example.com.    0       ANY     A
  newhost.example.com.    86400   IN      A       172.16.1.1