How to change the TTL on a specific DNS record

(Last modified: 17Jul2003)

This document (10085153) is provided subject to the disclaimer at the end of this document.

goal

fact

Novell DNS

fix

You can change the TTL on individual records either by the DNS BIND Export/Import or by editting the DNS record in ConsoleOne (done at your own risk)

EXPORT/IMPORT:
In the DNSDHCP Management console highlight the DNS Zone where the record resides that you are going to change. Click export, give it a path and filename that you will remember, after exporting the zone you will open it in a text editor, you might see the following:

$ORIGIN abc.com.
@   IN SOA ns1.abc.com. root.abc.com. (
     2003070203 ; Serial
     6000 ; Refresh
     3000 ; Retry
     90000 ; Expire
     43200 ) ; Minimum

$ORIGIN com.
abc IN NS ns1.abc.com.

$ORIGIN abc.com.
ns1 IN A 192.168.1.65

For any record that you would like to change the Minimum TTL on, just insert the number of seconds that you would like, eg.

ns1 60 IN A 192.168.1.65

Thus, the record "ns1.abc.com" will expire from other DNS servers after being cached for 60 seconds. ----REMEMBER to increment the SOA record (ie the serial number, in this example 2003070203, increment it by at least 1)

Then, in order to import the DNS zone again you will need to delete the existing zone, import your editted zone, then UNLOAD/LOAD NAMED.NLM.

If you do not with to do the safer export/import you can do the following procedure at your own risk:

EDITTING THE DNS RECORD IN CONSOLEONE:
Open ConsoleOne, browse to and click the zone object on the left, then on the right side of the screen all the DNS records will show up, double-click the record that you would like to modify, choose the other tab, select the plus button on the "DNIP:RR" record, underneath that you will see a long string of hex data, click or double-click the string until you get the box on right that looks like a browse button, click the "..." button, you will see a string of Hex data it will start with: 00 01 00 01 then NEXT FOUR HEX numbers are the TTL for that record, change at your own risk, but remember that it is HEX data in SECONDS that the record will expire.

After changing any records you will need to open the DNSDHCP Management console and increment the SOA of the zone, then AFTER SAVING THE CHANGES, UNLOAD/LOAD NAMED.NLM on the DNS server. You should then be able to do an NSLOOKUP, SET DEBUG, and query for the A record and see the TTL is the value that you set it to.

document

Document Title:	How to change the TTL on a specific DNS record
Document ID:	10085153
Solution ID:	NOVL91074
Creation Date:	16Jul2003
Modified Date:	17Jul2003
Novell Product Class:	NetWare

disclaimer

The Origin of this information may be internal or external to Novell. Novell makes all reasonable efforts to verify this information. However, the information provided in this document is for your information only. Novell makes no explicit or implied claims to the validity of this information.
Any trademarks referenced in this document are the property of their respective owners. Consult your product manuals for complete trademark information.