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I'm running a BIND9/Ubuntu DNS server on Amazon EC2. The DNS server was working great, until I decided to change the IP address on the server to a different one (using the elastic IP system.) Any ways I changed all of the "A", "NS", etc. records for the zone to point to the new IP address.

Three days later, the DNS hasn't updated... I'm not really sure where to go from here. I've ran the following command:

dig SOA example.com @b.gtld-servers.net

And it still returns the old IP address of the name server, plus the previous two IP addresses the zone used. What's the best way to resolve this issue? Is there any thing I can do at the domain registrar level?

  • Did you restart/reload the BIND server after editing zone files? – VL-80 May 15 '16 at 23:28
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In order to make changes to your DNS system run by ISC BIND server:

  1. Edit your zone files. Make whatever changes you were going to and do not forget to update the zone serial number. Without updating the serial number your changes will not be applied. Usually the serial number is made with following pattern YYYYMMDD00 (where last to digits increment if you change the zone multiple times in one day). In this way it also serves you as a reminder when last change to this zone was made.

  2. Issue a DNS server reload command - service bind9 reload (for Debian/Ubuntu). This will cause all config changes and zone files changes to be applied. Upon receiving this command the BIND server will also notify all secondary DNS servers (if appropriate configuration was made) about the fact that change was made so that they can transfer zone in order to stay up to date.

You can use dig or nslookup or host commands to debug DNS. Issue a direct DNS query to your primary and secondary server in order to see that changes have been applied:

dig hostname.domain @IP-ADDRESS

or

nslookup hostname.domain IP-ADDRESS

or

host hostname.domain IP-ADDRESS

where hostname.domain is the DNS record that was changed and IP-ADDRESS is the IP address of your DNS server (primary or secondary).

If everything went OK you should be able to see new address in the response from your servers.

After some time (depending on your zone cache and TTL settings) these changes will be propagated to the global DNS system. You can use same tools in order to query for example Google public DNS servers (8.8.8.8 and 8.8.4.4) and see if your change was successfully propagated (or not yet).

Regarding changes to the authoritative DNS server's IP addresses:

If you are updating the domain's authoritative servers addresses (NS records) you should make this change known to your domain registrar. Usually it can be done in the on-line control panel provided by the registrar. Your registrar may decide to test new servers for compliance to the DNS standards before applying the change. While it is done automatically it still could take some time.

  • This did the trick. I also had to register the IP address of my new custom name server with my domain registrar as well. – Mike Melusky May 16 '16 at 20:18

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