Subdomain doesn't resolve after adding it in cPanel when using remote nameservers

Symptoms

A subdomain added to cPanel isn't resolving when its main domain uses remote nameservers.

Description

When a subdomain is created in cPanel, an A record is created in the domain's local zone file. If the domain uses remote nameservers that are not configured in the "DNS Cluster" in WHM, the zone file on the remote (authoritative) nameservers will not be updated with the subdomain's DNS record.

Workaround

You must manually update the zones for domains that use remote nameservers. For cPanel to manage a domain's DNS records, the domain must use nameservers that resolve to the cPanel server or servers configured in the DNS cluster.

Additional resources

cPanel DNS Cluster Guide

How to configure nameservers in a cPanel & WHM server

How to set up nameservers with Domain Name Registrars