How to change the DNS of a domain name ? 
When you change your Web hosting provider, you must change the DNS (domain name servers) information for your domain name as well. The DNS information is specified by your hosting provider.
To modify the DNS of a domain registered with Aztus, use the domain management interface
[available here] 
.
Login to the interface using your username and password.
Once you are logged in, go to the "Name Servers" section found in the top menu to modify the DNS information.
Your domain name might be "locked" to prevent somebody else from stealing your domain. If your domain is "locked", you must request that we remove the "lock" before you can change the DNS information. You may verify if your domain lock is enabled or disabled in the "Domain Locking" section found in the top menu.
If the "lock" status is "Disabled", you may proceed.
If it is "Enabled", your domain is "locked" and you must ask us to change its status.
To modify the DNS information in the "Name Servers" section, replace the information configured in the interface by entering the Primary and Secondary DNS information provided by your new hosting company. Once you have entered the new DNS information, click on "Save Configuration" to confirm the modification.
When you are done, click on "Logout" from the top menu in order to logoff the domain management interface.
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http://www.aztus.com/en/domain/how_modify_dns.php
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