Configure DHCP for Dynamic DNS update to DNS Server in another tree.

Require Dynamic DNS updates from DHCP in one tree to DNS in another.

DHCP Configured in one Tree.
DNS Configured in second Tree

In the DHCP Tree :

1. Create a new object representing the remote DNS server. Using ConsoleOne :
a. Create new object of type DNIP: DNS Server
b. You will be prompted indicating there are no snapins for this type of object. Ignore this message.
c. Enter name in format DNS_
d. Edit the newly created DNS_ object in ConsoleOne.
e. Select the other tab and add an attribute of DNIP:ServerIPAddress.
f. Enter the IP address of the remote DNS server in HEX into the value of DNIP:ServerIPAddress attribute.

An example is :
04 AC 10 45 96 is IP 172.16.69.150 in HEX

Always begin 04
AC = 172
10 = 16
45 = 69
96 = 150

g. Save the object


2. Create a fake DNS Zone in the DHCP Tree.
a. Open the DNS/DHCP Management console
b. Click the DNS tab, create a new Zone.
c. Enter zone to be updated e.g. testzone.gov.uk
d. Select Primary for zone type.
e. Set Assigned Authorized DNS Server to None
f. Enter the DNS address of the server to be updated in the remote tree e.g. dnsserver.testzone.gov.uk
g. Save the zone.
h. Close the Management Console.


3. Edit the fake dns zone.
a. Open ConsoleOne, and edit the newly created testzone_gov_uk object that has been created.
b. Select the other tab, and add the following attribute :

DNIP: DesignatedServer

c. Edit the value, set to be the DNS server entry created in step 1.
d. Click OK to save the entry.


4.Update the DHCP for Dynamic Update
a. Open the DNSDHCP Management Console.
b. Click the DNS tab, select the zone created. Verify that the DNS Sever in the remote tree created in step 1 now shows as the "Designated Primary" server on the"attributes” tab.
c. Click the DHCP tab, select the subnet which is to have dynamic update enabled.
d. Select DNS Zone for dynamic update drop down list, and select the remote zone created for update.
e. Select the DNS range required, and then ensure the DNS Update option is set to always update.


5. Allow update from DCHP Server
a. Check the zone object in the remote tree containing the DNS Server. The "Allow Update” control list should allow the DHCP Sever to update the zone. The"Allow Update” should be either empty or contain the DHCP servers IP address. This ensures the update will be allowed.

6. Test
a. Unload DHCPSRVR.NLM and reload on the DHCP Server. Use LOAD DHCPSRVR -D2 to ensure debug is shown.
b. Try releasing and renewing a workstations IP address in that range. DHCP should attempt to update DNS with the host name. During this you should see similar to the following on the DHCP debug screen :

Connection to server 172.16.69.150, port 53
Reconstruct Connection: TCP Connect successful.
Sending first packet.
Credential accepted by DNS Sever

c. Once verified, DHCPSRVR should be loaded without the -D2 option for normal operation, as any debug switch has a small performance overhead.

Note: When testing clustered enabled DHCP, the resource should be cycled, rather than simply unloading and reloading DHCPSRVR.NLM.