Friday, May 30, 2014

DNS Stuff in 2008

In this class
*A Quick Overview of DNS
* What are DNS Zones really?
* The Different kinds of DNS records
* Forwarders and Roots Hints
* Globla Names Zones : The WINS Killer (Kind of)

*Domain Name Servcie (DNS) is a server 2008 Role thats basically a big phone book allowing users and computers to look up a Hosts IP address by using a Host name.
* The process of locating a computer via an IP address by looking it up by name is called Name Resolution.
* When computers (or Hosts) get assigned IP address by DHCP or by an administrator, they register their name and IP address with a DNS Server.
* The computer can now be found through the process of Name Resolution, and AD can now find users, computers, and other hosts by working in Conjuction with the DNS server.

What are DNS Zones really?
* A DNS zone is basically a Text file or Database that defines what machines it knows about in the "Namespace".
* There are 4 basic types of Zones you need to know about :
- * Recommended for Server 2008*
AD integrated Zone : DNS database is stored as an AD Object. No need for secondary Zones if all your DNS Servers are also DC's.
- Primary : Used in a Standalone DNS Server, it acts as a Master DNS Server that records and reads info.
- Secondary : A read only copy of a primary Zone. Must copy zone files from a DNS Server that has a primary zone.
- Stub : Only contains informations about other DNS Servers.

Why An AD integrated Zone?

* Let AD manage a lot of the DNS stuff for you!
* AD integrated Zones allow for :
- Zone transfers during AD replication
- Multimaster Replication
- Secure Dynamic Updates
- Backwards compatible to Secondary Zones (If you have any in your network)
* Forward Lookup Zones : Looks up a host IP address by name.
* Reversse lookup Zones : Looks up a host name by Ip address - used mostly for security and error checking.
* Conditional Forwarders : Used in place of Stub Zones to forward DNS requests about other Domains.

The Different Kinds of DNS Records


What contains in a DNS Zone?
* A (Host) : Name and IP address of a Host (Computer, network printer, PDA, etc)
* PTR (Pointer) : A record in a Reverse Zone.
* SOA (Start of Authority) : The begining record of a zone.
* SRV (Service Locator) : For Servers and Service Providing hosts.
* NS (Name Server) : A record that points to a DNS Server.
* MX (Mail Exchanger) : For Email Servers
* CNAME (Alisas) A "nickname" record that allows for multiple names for the same machine.

Forwarders and Root Hints:
* Root Hints allow your DNS Server to communicate with Name Servers on the Internet.
* A Forwarder can act in the place of root hints if your security requirements are higher.
- you need two DNS servers for this - One on the inside of your network perimeter that doesn't use Root Hints and one on the permiter that does.
- Internet DNS requests are forwarded out to the perimeter DNS Server by the internet DNS and then brought back in.

WINS
* WINS is an older technology that allows you to use NetBIOS for some Resolution.
* Most WINS server technology is being replaced by DNS for speed, reliability, and security.
* Global Name Zones are a NEW feature of Server 2008 for Single label Name Resolution.
* Use it for easy access intranet websites, and a potential replacement for WINS if you have older network-aware software applications still running that require WINS (Especially if you're rolling over to IPv6)
* WINS is still available on Server 2008 as a Feature (Not a role) if you need it.
* On your primary DNS Server, run this command to prepare your  DNS for global names:
dnscmd/ config /enableglobalnamesupport1
* Then create a new forward lookup zone called GlobalNames.
*Add CNAME Records for any web site or machine you want to have single lable resolution for.

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