Normally a zone’s SOA resource record displays the server holding the master copy of the zone in its primary server field. The server listed in this field is used by DHCP servers performing dynamic DNS updates. The default setting is Auto, which means that the primary server is hosting the master copy of the zone. In some situations it is necessary to use the name of a different server in the primary server field (for example, for load balancing). You can enter settings for the SOA resource record to override the default and specify a different primary server.
Modifying the Start of Authority primary server name can affect DDNS and Windows slaves. It is not recommended that the server be changed unless it is essential to do so.