> Describe the importance of DNS to AD ? Active Directory is dependent on DNS as a domain controller location mechanism and uses DNS domain
naming conventions in the architecture of Active Directory domains. There are three components in the
dependency of Active Directory on DNS.
1.Domain controller locator (Locator):-
The Windows Server 2003 or later domain controller locator, implemented in the Net Logon service, enables a client to locate a domain controller.
2. Active Directory domain names in DNS:-
Every Windows Server 2003 or later Active Directory domain has a DNS domain name (for example,
techievalley.com), and every Windows Server 2003 or later based computer has a DNS name (for example,win2k8server.techievalley.com). Architecturally, domains and computers are represented both as objects in Active Directory and as nodes in DNS.
3. Active Directory DNS objects:-
When DNS data is stored in Active Directory, each DNS zone is an Active Directory container object
(class dnsZone). The dnsZone object contains a DNS node object (class dnsNode) for every unique name
within that zone. These unique names include the variations assigned to a specific host computer when
it unctions, for example, as a primary domain controller or as a global catalog server. The dnsNode
object has a dnsRecord multivalue attribute that contains a value for every resource record that is
associated with an object’s name.
> What is Forwarding in DNS?
A forwarder is a feature in DNS server that is used to forward DNS queries for external DNS names to DNS servers outside of that network. We ca configure a DNS server as a forwarder to forward the name query to other DNS servers in the network when they cannot resolve locally to that DNS server.
> What are Queries types in DNS? 1. Recursive Query: This name queries are generally made by a DNS client to a DNS server or by a DNS server that is configured to pass unresolved name queries to another DNS server, in the case of a DNS server configured to use a forwarder.
2. Iterative Query: An iterative name query is one in which a DNS client allows the DNS server to return the best answer it can give based on its cache or zone data. If the queried DNS server does not have an exact match for the queried name, the best possible information it can return is a referral. The DNS client can then query the DNS server for which it obtained a referral. It continues this process until it locates a DNS server that is authoritative for the queried name, or until an error or time-out condition is met.
> What are Tools for troubleshooting of DNS?
DNS Console, NSLOOKUP, DNSCMD, IPCONFIG, DNS Logs.
> How to check DNS health?
Using the DCdiag.
Eg:- dcdiag /test:dns /v /e