DNS Types of Zone

DNS Zones:

There are two types of zones, forward lookup & reverse lookup. Forward lookup zones contain information needed to resolve names within the DNS domain. They must include SOA & NS records and can include any type of resource record to expect the PTR resource record. Reverse lookup zones contain information needed to perform reverse lookups. They usually include SOA, NS, PTR, & CNAME records.

1. Primary Zone (MASTER): Primary zones are created on the primary DNS servers. It is a read /writescopy of zone. A primary DNS server is responsible for reading data related to the domain.

Configuring a primary zone:

On DC
Start – p – admin tools – DNS – create a zone & host record

2. Secondary Zone (SLAVE): Secondary zone to copy read-only zone data from another server

Secondary zone servers accomplish four tasks.

1. Fault tolerance

2. Load balancing to the primary zone

3. Backup for primary zone

4. Reduce name resolution traffic over WAN links

Creating a secondary zone:

On Member server If DNS is not available install DNS first
Open DNS – right click on FLZ
new zone – next – specify the primary – DNS servers IP address –add – next – finish

3. Stub zone: Stub zone is a newly added feature in WIN 2003. Stub zone contains a copy of name server and SOA records used for reducing the DNS search orders. Provides fault tolerance and load balancing. Stub zones are useful for resolving the query faster. It is not authoritative, used to Keep delegated zone info current.

How to know whether the recent changes in Primary zone are updated to secondary zone or not?

Compare the Serial Number on Start of Authority tab in both secondary on primary DNS zone properties.

If both are same then recent updates are made to secondary zone.

If not (i.e., secondary is less then primary) click on “Transfer from Master