What makes a zone Read-Only? - BlueCat Address Manager - 9.0.0

Address Manager Administration Guide

BlueCat Address Manager

The mode of the primary server, or AD-integrated elect determines whether the zone is Read-Only or Read-Write.

For example, if the server with the primary role is in Read-Only mode and one or more of the servers with the secondary roles are in Read-Write mode, the zone is still considered to be a Read-Only zone.