When it comes to studying for this exam objective, your main focus should definitely be on installing and configuring DHCP (although this is not to say that you can ignore the other sub-objectives). So let’s take a look at some of the important things you need to know when it comes to DHCP.

Installing DHCP is a simple process and it can be done using a few different methods. One method is to use the Add or Remove Programs applet within the Control Panel.

1. Click Start, point to Control Panel, and click Add/Remove Programs.
2. Click Add/Remove Windows Components.
3. From the list of Components select Networking Services and click the Details button.
4. Select Dynamic Host Configuration Protocol from the list of Networking Services.
5. Click OK.
6. Click Next to continue.
7. Click Finish.

You absolutely need to know how to authorize a DHCP server and you should understand the whole authorization process. This feature was first introduced in Windows 2000. It is designed to prevent any rogue DHCP servers from appearing on the network since a DHCP server with incorrect scope information can wreak havoc on a network.

Authorizing a DHCP server is a very straight forward process. Remember though that in order to complete the steps outlined below, you must be a member of the Enterprise Admins group.

1. Click Start, point to Administrative Tools, and select DHCP.
2. Within the DHCP management console, right click the DHCP server and click Authorize. Any server not yet authorized will appear with a red arrow beside it.
3. Once the server has been successfully authorized within Active Directory, it will appear with a green arrow beside it.

You should also know that if a DHCP server has not been authorized, the DHCP service will stop and the server will be unable to lease IP addresses to clients.

Still on the topic of DHCP, you need to remember that DHCP servers do not share any scope information. This means one DHCP server will be unaware of the scopes configured on another DHCP server. With this in mind, when it comes to implementing the 80/20 rule for fault tolerance, the scopes cannot overlap or you may run into duplicate IP addresses on the network. With the 80/20 rule, 80% of the IP addresses for a subnet are added to a scope on one DHCP server. The remaining 20% are added to a scope on another DHCP server for fault tolerance.