Installing DHCP in Windows Server 2008 is as simple as adding another role to a server. Some additional steps must be taken, however, to authorize the DHCP server. Back in Windows 2000 Server, Microsoft introduced the concept of authorizing a DHCP server. Microsoft did this because of the problem of “rogue” DHCP servers—servers that users would install on the network, and configure to hand out IP addresses, thus causing problems with production DNS servers. The problem with rogue DHCP servers was that IP addresses that were handed out would either:
• Overlap with existing IP addresses in the network, causing a conflict
• Hand out correct IP addresses, but possibly hand out other incorrect information, such as DNS, WINS, Subnet Mask, and Gateway information
• Hand out a completely incorrect range of IP addresses
• Create unnecessary traffic on the network
During the installation process, we will walk through installing the DHCP role, configuring DHCP settings, and authorizing the DHCP server. Let’s begin.
1. Choose Start | Administrative Tools | Server Manager.
2. Scroll down to Role Summary and click Add Roles.
3. When the Before You Begin page opens, click Next.
4. On the Select Server Roles page, select DHCP Server, and then
5. Click Next to get through the DNS Server settings. This screen is verifying
the IP address of our DNS server, which will be passed to clients.
6. Click Next again to skip the WINS settings. If WINS was running (we will
discuss WINS later), we could select the WINS server here.
Next, we need to configure a DHCP scope. A DHCP scope is a range of IP addresses (as well as additional IP options, such as gateway, DNS servers, and WINS servers) that can be handed out by a DHCP server. In the first example, we are going to configure both an IPv4 and IPv6 scope.
Now, let’s configure our scope:
1. Click Add… to add a new DHCP Scope.
2. In the Scope Name field, type Internal Scope.
3. In the Starting IP Address field, type 192.168.1.200, or any IP range you have available on your network.
4. In the Ending IP Address field, type the end of your scope. We will use 192.168.1.220.
5. In the Subnet Mask field, enter the subnet mask of your network. Our subnet mask is 255.255.255.0.
6. Skip the default gateway for now, we will add this later.
7. Choose Wired as the Subnet type, but click the down arrow to see the Wireless option.
8. Verify that Activate This Scope is checked, and then click OK.
9. Click Next once your scope is added.
10. Determine what to do with IPv6 clients. We want to manage IPv6 clients through DHCP when necessary. To do this, select Disable DHCPv6 Stateless Mode For This Server and click Next.
11. Specify the IP address of an IPv6-enabled DNS server. To do this, enter the IP address of this server. If you recall, we set IPv6 options in the DNS section. Verify that our server’s IPv6 settings appear in the Preferred DNS Server IPv6 Address, validate it, and then click Next.
12. On the Authorize DHCP Server, you can specify the credentials of an authorized user, or just click Next.
13. Click Install to begin the installation.
14. When installation is complete, click Close.
Source of Information : Syngress The Best Damn Windows Server 2008 Book Period 2nd Edition