Secondary DNS servers transfer their zone information directly from the primary DNS server and keep a copy locally.

辅助DNS服务器直接从主dNS服务器传输其区域信息，并在本地保留副本。

youdao

Secondary DNS servers transfer their zone information directly from the primary DNS server and keep a copy locally.

辅助DNS服务器直接从主dNS服务器传输其区域信息，并在本地保留副本。

youdao