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Thursday, March 10, 2011

Installing , Configuring and Backup/Restore of DHCP Server Role in Windows 2000/2003/2008 Server

Install , Configure , Backup and Restore DHCP Server in windows 2000/2003/2008 Server.

In my last post we has seen basic of DHCP server , today we will see how to install, configure take a backup of DHCP server and how to Restore it from last backup.

Before installing DHCP Server you should Configure your server with static IP Address.


Scope: - A DHCP scope determines which IP addresses are allocated to clients. A scope defines a set of IP addresses and associated configuration information that can be supplied to a DHCP client. A scope must be defined and activated before DHCP clients can use the DHCP server for dynamic TCP/IP configuration. You can configure as many scopes on a DHCP server as needed for your network environment.

exclusion range—one or more IP addresses in the scope that are should not be assign to  DHCP clients.

 
Installing DHCP server on windows 2000/ 2003 Server

  1. Log on as the Administrator
  2. Click Start Run And Type appwiz.cpl it will open  Add /OR Remove program windows.
  3. In Add/Or Remove Program windows Select Add /Remove Windows Component from left side button. It will open Windows component in new window.
  4. In new windows component select networking Services and click Detail at bottom it will open networking services window ,
  5. In networking services windows click mark on Dynamic Host configuration Protocol service (DHCP) and click OK. It will install DHCP server service on your computer when installing it will ask you for Operating system CD (2000 /2003)
  6. After install click ok , ok and close all windows .(Now DHCP server Role is installed on your system)

 
Configuring DHCP server on windows 2000/2003/2008 server.


  1. To configure DHCP server log on as administrator
  2. Click on Start – Administrative tool – DHCP MMC snap-in
  3. In DHCP MMC snap-in select your server
  4. Right Click the server and select New Scope this will open new window for scope name and description  type the scope name and description and click next.
  5. In IP address range window inter the range of ip address that should this dhcp server use to assign the IP between For eg.
  Starting IP Address: 192.168.15.101
Ending IP Address: 192.168.15.254
Subnet Mask: 255.255.255.0
  1. after entering IP range and subnet mask information click Next. It will open new window asking for Configure DHCP Option click yes ,I want to configure these option now and Click Next.
  2. Next Windows ask you to provide Default getaway information , enter you router ip address or default Gateway ip address (it may be your router, firewall or nating server ip address) Click Next (optional)
  3. On Domain name and DNS server window inter you domain name and ip address of  DNS servers. And click next (Optional )
  4. On WINS server window inter the information of your wins server ip address. And click next.
  5. Active Scope windows will appear if you want to activate the scope now click on Yes,I want to activate the scope now else no. and click Next. And last click Finish

Authorizing DHCP in Active Directory Domain.

      (you must Authorize DHCP server to provide TCP/IP information to the client)
  1. To Authorize DHCP server in Active Directory You should be the member of Enterprise Admin group and local Administrator user group.
  2. Open DHCP MMC Snap-in from Start- Administrative Tools- DHCP
  3. In DHCP MMC Snap-in windows select and Right click on server , you want to authorize  and in that select authorize and refresh the DHCP window the icon of your server become green means this server is authorize to provide DHCP Client request.  

Adding the DHCP Server Role on Windows Server 2008
1. log on as the administrator of the local computer.
2. Open The Server Manager from Start – Server Manager , Server Manager windos appear. Expand the Server Manager
window to full-screen if necessary.
3. In the left-hand pane of Server Manager, double-click Roles.
4. Click Add Role. Click Next to bypass Welcome screen.
5. The Select Server Roles screen appears. Place a checkmark next to DHCP Server.
Click Next.
6. The Introduction to DHCP Server screen appears. click Next.
7. The Specify IPv4 DNS Server Settings screen appears. Enter the DNS Server IP Address information for your network configuration and click Next.
8. The Specify IPv4 WINS Server Settings screen appears. Enter WINS server IP Address for your network and click Next.
9. The Add or Edit DHCP Scopes screen appears. Click Add to create a DHCP scope
10. The Add Scope screen appears. Enter the appropriate information for your network
configuration, for example:
Name: Example_Network
Starting IP Address: 192.168.15.101
Ending IP Address: 192.168.15.254
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.1.1
Subnet type: Wired
11. Ensure that there is a checkmark next to Activate this scope, and then click OK. Click Next
12. The Configure DHCPv6 Stateless Mode screen appears. If You want to also use IPv6 then Select Enable Else Select Disable and click Next. If you enable follow the stapes like IPv4 to configure  click Next.
13. The Authorize DHCP Server screen appears. Select authorize this DHCP
server in AD DS and click Next.

 (Note: to authorize is Active Directory user must having enterprise admin group. You must authorize a DHCP server in Active Directory before the server can issue leases to DHCP clients.)

14. The Confirm Installation Selections screen appears. Click Install.

 BACK UP DHCP Server 

1. In the DHCP console, in the console tree, select the appropriate DHCP server.
2. Right-click the server and click Backup.
3. In the Browse For Folder dialog box, select the appropriate folder to back up to,
and then click OK
 
 
OR by command line

netsh dhcp server backup "C:\DHCPbackups.dmp


RESTORE DHCP SERVER 

To restore the DHCP database, right-click the server and click Restore.
1. In the Browse For Folder dialog box, select the folder where the backup resides
and then click OK.
2. In the DHCP dialog box, click Yes to stop and then restart the service.
3. If the status of the service does not update, press F5 to refresh the DHCP console

OR by command line
netsh exec C:\ DHCPbackups.dmp
 

(In next post we will see how to install , Configure, backup and restore on Windows 2008 Core Server)


Wednesday, March 9, 2011

DHCP Server Basic

DHCP Server Basic 

What is DHCP Server?

       The Purpose of DHCP server in Network is to provide the TCP/IP Configuration to the Client. DHCP free up System Administrator from Manually configuring each host on the network. and quickly configure changes in a network configuration. And In The larger network, the greater benefit of using DHCP is that you do not need manually configure and maintain the record  Without dynamic address assignment, each host has to be configured manually and IP addresses must be carefully managed to avoid duplication or miss configuration.

      And Because settings and information are stored centrally, you can quickly and easily add or change a client setting (for example, the IP address of an alternate DNS server) for all clients on your network from a single location. Without a centralized database of configuration information, it is difficult to maintain a current view of the host settings or to change them.

DHCP provides five key benefits to those managing and maintaining a TCP/IP network:-
  1. Centralized administration of IP configuration:- DHCP IP configuration information
    can be stored in one location, enabling the administrator to centrally manage it. A DHCP
    server tracks all leased and reserved IP addresses and lists them in the DHCP console. You
    can use the DHCP console to determine the IP addresses of all DHCP-enabled devices on
    your network.
  2. Dynamic host configuration:- DHCP Server Automatically configure Host and update the changes dynamically.
  3. Seamless IP host configuration: -The use of DHCP ensures that DHCP clients get accurate and timely IP configuration parameters, such as the IP address, subnet mask, default gateway, IP address of the DNS server, and so on, without user intervention. Because the configuration is automatic, troubleshooting of miss configurations, such as mistyped numbers, is largely eliminated.
  4. Scalabilit :- As Scalability is censor  DHCP is Scala for both small and very large network.
  5. Flexibility :- Using DHCP gives the administrator increased flexibility, allowing the
    administrator to more easily change IP configurations when the infrastructure changes.
It provide following information to client but not limited to it. It Provide more than 70 TCP/IP configuration settings.
  • IP Address.
  • Subnet Mask
  • Default Gateway
  • DNS Domain Name
  • Address of DNS Server
  • Address of WINS Server.
  • And many more
How it Work ? OR DHCP Client And Server in DORA Process

      When you turn on DHCP on Client Computer to get TCP/IP information from DHCP Server. there are some communication will get between DHCP Client and DHCP Server. this process are called as DHCP DORA Process. DORA Means Discover, Offer, Request and acknowledgment .


  1. Discover: -When you turn on DHCP on client computer to get TCP/IP information from DHCP server. because client do not having IP address information about DHCP server to get TCP/IP information .It send broadcasts packet in a network to find DHCP server who can give him TCP/IP information.
  2. Offer: - If in network there are DHCP server running . All  DHCP server Responds to the broadcast by sending Offer Packet because Client do not having IP Address it also broadcasts back to client by offering TCP/IP configuration. (DHCP server ask Client for confirmation that it is ready to accept the offer else that IP address will be provided to other clients.)
  3. Request : - So Client computer responds with first DHCP offer by sending  Request Packet. for acceptance and because other Server not got any confirmation by client it know that client has not accecpted our offer so we can be able to give ipaddress to other client.DHCP Request packet are  uni cast packet because now client know IP address of DHCP server to contact. 
  4. Acknowledgment :- After receiving  the request packet DHCP Server send Acknowledgment packet to client that it can use this IP address .

(In next post we will see how to install, Configure and backup DHCP server in windows 2003 and 2008 server)