This section describes how to integrate Plesk with an external Linux-based secondary (slave) DNS server. This server will copy the zone data from your primary DNS server, but cannot change that data.

The integration can be performed using the Slave DNS Manager extension available in the Extensions Catalog in the Plesk GUI.

Configure a secondary (slave) DNS server:

1. Install BIND if it is not already installed. BIND is an open-source DNS management software program. You can check if it is installed in the :doc:`Services Management <59418>` interface in the Tools & Settings > Server Management > Services Management section, where it appears as “DNS Server (BIND)”. If BIND is not installed, you can install it with the following command:

   apt-get install bind9
   

2. In the named.conf file on the secondary DNS server, add the following required information:

   • The enabled allow-new-zones option in the options directive. If this directive does not exist, you can add it.
   • A secret key.
   • The IP address of the primary DNS server and an instruction for BIND to accept connections from it.

   Your named.conf file additions will look like the following example:

   options {
       ...
   allow-new-zones yes;
    };
   key "rndc-key-10.69.43.240" {
   algorithm hmac-sha256;
   secret "YTQ2OGZiY2E4MDliMTY5OThkOGYyYw==";
   };
   controls {
   inet * port 953 allow { 10.69.43.240; 127.0.0.1; } keys { "rndc-key-10.69.43.240"; };
   };
   

3. Save your named.conf changes, then restart the BIND service by issuing the following command:

   invoke-rc.d bind9 restart
   

4. To make sure that you have a copy of your secret key available, add it to the /etc/bind/rndc.key file. For example:

   key "rndc-key" {
       algorithm hmac-md5;
       secret "vwOxonI4n4CVRUhKAOAAIA==";
    };
   

That’s it, the secondary name server is set up.

Configure Plesk for a secondary (slave) DNS server:

To configure Plesk to recognize your secondary DNS server, add it in the Slave DNS Manager extension.

Add the secondary server and specify its IP address and the secret key. The extension will create a configuration file with the secondary server settings for the rndc utility.

From now on, Plesk will automatically use the following commands to transfer all created, modified, and deleted zones to the secondary server:

Creation

/usr/sbin/rndc -c slave.config addzone example.com '{ type slave; file "/var/lib/bind/example.com"; masters { <plesk_ip>; }; };'

Modification

/usr/sbin/rndc -c slave.config refresh example.com

Deletion

/usr/sbin/rndc -c slave.config delzone example.com

Now, when you add a domain in Plesk, a DNS zone is automatically created on the secondary server as well as on the primary server.

More information about the extension’s algorithm:

The Slave DNS Manager extension works according to the following algorithm:

1. It registers a secondary server in the extension settings.
2. The secondary server’s IP address is automatically added to the list of addresses that are allowed to transfer domain zones from the Plesk server.
3. When you create, modify, or delete an active domain zone in Plesk, Plesk creates, modifies, or deletes the domain zone in the local DNS service.
4. The script starts and receives the domain name and the command to create, modify, or delete a domain zone.
5. The script initiates the rndc command for each connected secondary server.
6. Secondary servers synchronize domain zones with the ones on the Plesk server.