server interview -2

What is DNS? How it works?
Domain Name System (DNS)

DNS provides a service for mapping DNS domain names to IP addresses, and vice versa. 

This allows users, computers, and applications to query the DNS to specify remote systems

 by fully qualified domain names rather than by IP addresses.

What is DNS & WINS

DNS is a Domain Naming System, which resolves Host names to IP        

addresses. It uses fully qualified domain names. DNS is a Internet standard used

to resolve host names WINS is a Windows Internet Name Service, which

resolves Netbios names to IP Address. This is proprietary for Windows

  

Types of DNS Servers

 Primary DNS

 Secondary DNS

 Active Directory Integrated DNS

 Forwarder

 Caching only DNS

Can i have all DNS Records?

A, AAAA/IPv6, CNAME, MX, NS, PTR, SOA, SRV, TXT

A--- IPv4 Address record. An IPv4 address for a host.

AAAA-- IPv6 Address record. An IPv6 address for a host. Current IETF recommendation for IPv6 forward-mapped zones.

CNAME--- Canonical Name. An alias name for a host.

MX---- Mail Exchanger. A preference value and the host name for a mail server/exchanger that will service this zone. RFC 974 defines valid names.

NS-- Name Server. Defines the authoritative name.

PTR--- IP address (IPv4 or IPv6) to host. Used in reverse maps.

SOA----- Start of Authority. Defines the zone name, an e-mail contact and various time and refresh values applicable to the zone.

SRV--- Defines services available in zone e.g. ldap, http etc..

TXT---- Text information associated with a name. The SPF record is defined using a TXT record but is not (July 2004) an IETF RFC.

what is TTL & how to set TTL time in DNS

TTL is Time to Live setting used for the amount of time that the record

should remain in cache when name resolution happened.

We can set TTL in SOA (start of authority record) of DNS

How to take DNS and WINS,DHCP backup

%System root%/system32/dns

%System root%/system32/WINS

%System root%/system32/DHCP

What is Forward and reverse lookup zone?

The DNS Forward Lookup zone is used to resolve computer host names

 to an IP address ("forward name resolution").

The Reverse Lookup zone resolves IP addresses to computer host names in the

DNS namespace ("reverse name resolution").

What is SOA Record

SOA is a Start Of Authority record, which is a first record in DNS, which controls

the startup behavior of DNS. We can configure TTL, refresh, and retry intervals

in this record.