DNS Server

As read in my previous blog about Stub Zones, In this blog we will study more about different types of DNS Zones. In Windows 2003 Server we can find 4 types of DNS Zones. viz

a. Primary Zones : Primary Zones are a read/write copy and can be created on any Server with DNS component installed.

b. Secondary Zones : Secondary Zones can store read-only copy of the of the DNS server.

c. Active Directory Zones : Active Directory Integrated Zone is a secured read/write copy of DNS database that can only be created on Domain Controller, the DNS database is integrated with Active directory database i.e. ntds.dit, thus providing state of class encryption and security to DNS database which otherwise is vulnerable to attack consequently raising security concerns.

d. Stub Zones

In DNS ,replication is addressed as Zone Transfers, zone transfers happen in secure encrypted mode. In primary and secondary zone transfers ,the secondary copies the whole copy of the primary database. In Active Directory Integrated Zone the initial transfer is full transfer which is referred as AXPR and incremental which is referred as IXPR thereafter.

Some lesser known facts about DNS

· WINS is replacement for LMHOST, similarly DNS is replacement for HOST file.

· WinNT supports only primary and secondary DNS database, Windows NT is a static DNS,where as Windows 2000 and 2003 support Dynamic DNS.

· AD and DNS are mutually dependent ,AD needs DNS for name resolution and DNS needs AD for security.

Basic Architecture for Implemeting DHCP Relay Agent Concept in Lab Environment

Find more on this architecture with step by step process in implementing the DHCP Relay Agent Service.

DNS and Active Directory

DNS and Active Directory are complimentary to each other, Active directory relies on DNS for name resolution, in fact DNS is the prerequisite for AD to function, in return Active Directory provide safe haven for DNS database as the DNS zone information can be integrated with Active Directory database thus providing best class encryption and security.

Points to remember when it comes to DNS integration.

DNS in Windows 2003 support 4 types of Zones.

• Primary Zone
• Secondary Zone
• Stub Zone
• Active Directory Integrated Zone

Difference between primary

Primary Zone holds read/write copy of DNS database and can be created on any server with DNS component.

Secondary zone holds read only copy of the database, and updates its entries from primary server, in Windows domain environment the replication happens during domain replication process.

Stub zones doesn’t hold the complete database as Secondary zone, but stores the copies of Name Server and SOA records and A records for all name servers authoritative for the zone.

Stub zones are basically configured at remote sites with low bandwidth connectivity with parent network, Stub zones accepts the request from client within the site and forwards the request to Name server and shares the information received from Name Servers, this information cached for future use.

You will find more about Active Directory Integrated Zone in my next blog….

The differences between FTP and TFTP

The differences are :

FTP is a complete, session-oriented, general purpose file transfer protocol.
TFTP is used as a bare-bones special purpose file transfer protocol.
FTP can be used interactively. TFTP allows only unidirectional transfer of files.
FTP depends on TCP, is connection oriented, and provides reliable control. 
TFTP depends on UDP, requires less overhead, and provides virtually no control.
FTP provides user authentication. TFTP does not.
FTP uses well-known TCP port numbers: 20 for data and 21 for connection dialog. 
TFTP operates at UDP port number 69 for its file transfer activity.
The Windows NT FTP server service does not support TFTP because TFTP does not support any authentication.Windows 95 and TCP/IP-32 for Windows for Workgroups do not include a TFTP client program.

Difference between Windows 2000 and Windows 2003 Server.

Difference between Windows 2000 and Windows 2003 Server.
Following are the extra features you will find in Win 2003.
• IIS 6.0 [Win 2000 –IIS 5.0]
• Domain & forest renaming,
• LDAP version is different 
• Stub zone option in DNS introduced in Win 2003
• ASR option replaced ERD
• IE 6.0 [Win 2000 – IE 5.0]
• 64 Bit O/S Support
• Schema Version changed.
• Volume shadow copy introduced,
• Cross forest trust relationship introduced,
• Win 2003 Support 8 node clustering [Win 2000 supports 4 Node]
• Code name is Win 2003 is Win NT 5.1 [Win 2000 NT 5.0]
• Win 2003 has built support for IPV6 
• Windows 2003 Supports Microsoft .NET 2.0
• Distributed File system was introduced in Windows 2003 Server
• Support for GUID partition table for 64 bit architecture integration
• Win 2003 supports 4 types of domain functionality 
Domain functional level        Domain controllers supported
Windows 2000 mixed (default) Windows NT 4.0
                                         Windows 2000
                                         Windows Server 2003 family
Windows 2000 native             Windows 2000
                                         Windows Server 2003 family
Windows Server 2003 interim   Windows NT 4.0
                                         Windows Server 2003 family
Windows Server 2003            Windows Server 2003 family
 

WINS [Points to Remember]

WINS [Points to Remember]

1. The NetBIOS name can have max of 16 characters, while adding to domain max of 15 characters are recommended because the domain adds the $ sign as suffix taking total to 16.
2. NBT (NetBIOS over TCP/IP) Runs over TCP/IP by default.
3. LMHOST (LAN Manager Host) is file available in local machine (C:\WINDOWS\system32\drivers\etc) ,consists of hostname entries mapped to ip address (its basically first step of troubleshooting for name resolution issues in local network)

Name Resolution Search Order
Search Order B-Node – Broadcast (Configured by default when WINS server is not configured in the network)
• Local resolved cache 
• LM Host File
• Broadcast

Search Order for P-Node 
• Local resolved cache 
• LM Host File
• WINS Server

Search Order for M-Node (Mixed)
• Local resolved cache 
• LM Host File
• Broadcast
• WINS Server

Search Order for H-Node (Hybrid) 
(Configured by default when WINS server IP is configured in DHCP Server Options)
• Local resolved cache 
• LM Host File
• WINS Server
• Broadcast

WINS Funda

What is WINS ?
A. WINS is abbreviation for Windows Internet Naming Service, WINS protocol operates at port 43.
The WINS server is basically involved in name querying ie the NetBIOS name is resolved to equivalent IP address.

Q. What are the different NetBIOS node type and what is its importance.
A. A NetBIOS node type is technique of resolving the NetBIOS name to ip address.
There are basically four types of nodes, viz,

1. B-Node (Broadcast) – Client broadcast to whole network for NetBIOS name resolution , creates unnecessary traffic in the network.typically all these broadcast are blocked at router interface.
2. P-Node (WINS server) –Client contacts the Wins server for name resolution and if the wins server has failed or if it is not available ,the process fails to resolve the NetBIOS name
3. M-Node (Mixed node -combination of B and P Nodes) Broadcast first and later contact the wins server.(not recommended)
4. H-Node (Hybrid node- combination of P and B Nodes) Contact the wins server first ,and if the query fails then broadcast –Default if the wins server is configured in the network

Read more about wins in my next posting

Aborting the abnormal shutdown.......

At times we all must have come across the some abnormal shutdown message displayed,

To abort this process and try this command to ge the control of your computer by aborting this system generated process.

To abort such abnormal shutdown ,execute the following command from the command prompt.

The follow this path to execute the same 

Start --> Run -->cmd -->C:\-->cd windows -->c:\windows>shutdown -a