How to integrate primary Plesk DNS server with secondary Slave DNS server?
Plesk as Master DNS + external Linux-based DNS server
Plesk as Master DNS + DNS on a cloud service
Plesk as Master DNS + another Plesk as slave DNS
If the Slave server has Plesk installed, there is no need to install Slave DNS Manager extension.
Perform the following steps:
Add IP of the Slave DNS in the master DNS server in Tools & Settings > DNS Template > Transfer Restrictions Template
Create the same domains in both Master and Slave Plesk servers.
Warning: The same domains should exist on both master and slave Plesk servers. It prevents DNS data from getting corrupted.
Change DNS to Slave mode on Slave server side in Domains > example.com > DNS Settings > Switch to Slave.