NOTIFY messages are not sent by Plesk server to NS server specified in a SOA record

Symptoms

• Plesk server is acting as hidden DNS master server: external NS servers are specified in Tools & Settings > DNS Settings (or DNS Template) and all zones created in Plesk are propagated to these servers. They are serving all DNS requests for domains hosted on the Plesk server.
• One of this external NS servers is added to a SOA record as a primary master nameserver.
• Changes in DNS zones (or notifies) are not sent to the NS server specified in an SOA record.

Cause

This is the expected behavior of the BIND DNS server. The following can be found in the BIND 9 Administrator Reference Manual:

PLESK_INFO: Normally a NOTIFY message is not sent to the SOA MNAME (SOA ORIGIN) as it is supposed to contain the name of the ultimate master.

Resolution

On Plesk servers using BIND as the DNS server, the “notify-to-soa” option is in effect since Plesk 18.0.42.

Install the latest Plesk updates.