Windows DNS Interviews Question and Answer Part 1

DNS (Domain Naming System or Distributed Naming System) Related Interview Question & Answer.

1) What is DNS?

The Domain Name System (DNS) is a hierarchical distributed naming system for computers. The Domain Name System distributes the responsibility of assigning domain names and mapping those names to IP addresses by designating authoritative name servers for each domain. Authoritative name servers are assigned to be responsible for their particular domains, and in turn can assign other authoritative name servers for their sub-domains.

2) What is the main purpose of a DNS server?

DNS servers are used to resolve FQDN hostnames into IP addresses and vice versa.

3) How does a computer know to which DNS server it has to sent the request

The DNS server IP address is configured on the TCP/IP adapter setting of the computer. With this information, the computer knows the DNS server to which the request has to be sent.

4) What is the port no of DNS?

UDP port number - 53

5) How many root DNS servers are available in the world?
13

6) What is a Forward Lookup?

Resolving Host Names to IP Addresses, Address mapping (A) records maps a host name to an IP address

7) What is a Forward Lookup?

Reverse-lookup pointer (PTR) records map an IP address to a host name.

8) What is a Resource Record?

It is a record provides the information about the resources available in the N/W infrastructure.