Final answer:
A Secondary DNS Zone is a backup copy of a primary DNS zone that provides redundancy and fault tolerance. It ensures that even if the primary DNS server goes down, the secondary server can still provide DNS services.
Step-by-step explanation:
A Secondary DNS Zone is a backup copy of a primary DNS zone. It provides redundancy and fault tolerance by allowing multiple DNS servers to hold copies of the same zone. This means that if the primary DNS server goes down, the secondary DNS server can still respond to queries and resolve domain names.
For example, imagine a company that has two DNS servers, one primary and one secondary. The primary DNS server is responsible for hosting the company's DNS zone and responding to DNS queries. The secondary DNS server holds a copy of the zone and can act as a backup if the primary server fails. This ensures that even if the primary server is unavailable, the secondary server can still provide DNS services.