From the DHCP console, you have complete control over the DHCP server’s configuration and operation. The following paragraphs summarize some of
the things that you can do from the DHCP console:
⻬ You can authorize the DHCP server, which allows it to begin assigning client IP addresses. To authorize a server, select the server, choose
Action➪Manage Authorized Servers, and click Authorize. ⻬ To add another scope, right-click the server in the tree and choose the
New Scope command from the menu that appears. This brings up the New Scope Wizard so you can create a new scope.
⻬ To activate or deactivate a scope, right-click the scope in the tree and choose the Activate or Deactivate command.
⻬ To change scope settings, right-click the scope and choose the Properties command. This brings up the Scope Properties dialog box which lets
you change the scope’s starting and ending IP addresses, subnet mask, and DNS configuration.
⻬ To change the scope exclusions, click Address Pool under the scope in the tree. This will list each range of addresses that’s included in the
scope. You can add or delete a range by right-clicking the range and choosing the Delete command from the menu that appears. You can also
add a new exclusion range by right-clicking Address Pool in the tree and choosing Add New Exclusion from the pop-up menu.
⻬ To view or change reservations, click Reservations in the tree. ⻬ To view a list of the addresses that are currently assigned, click Address
Leases in the tree.
Figure 25-2:
The DHCP manage-
ment console.
351
Chapter 25: Configuring Your Network for DHCP
How to Configure a Windows DHCP Client
Configuring a Windows client for DHCP is easy. The DHCP client is automati- cally included when you install the TCPIP protocol, so all you have to do is
configure TCPIP to use DHCP. To do this, bring up the Network Properties dialog box by choosing Network or Network Connections in the Control Panel
depending on which version of Windows the client is running. Then, select the TCPIP protocol and click the Properties button. This brings up the TCPIP
Properties dialog box. To configure the computer to use DHCP, check Obtain an IP Address Automatically and Obtain DNS Server Address Automatically.
Renewing and Releasing Leases
Normally, a DHCP client attempts to renew its lease when the lease is halfway to the point of being expired. For example, if a client obtains an eight-day
lease, it attempts to renew the lease after four days. If necessary, you can renew a lease sooner by issuing the ipconfig renew command at a com-
mand prompt. You may want to do this if you’ve changed the scope’s config- uration or if the client’s IP configuration isn’t working correctly.
You can also release a DHCP lease by issuing the ipconfig release com- mand at a command prompt. When you release a lease, the client computer no
longer has a valid IP address. This is shown in the output from the ipconfig release
command: C:\ipconfig release
Windows IP Configuration Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . : IP Address. . . . . . . . . . . . : 0.0.0.0
Subnet Mask . . . . . . . . . . . : 0.0.0.0 Default Gateway . . . . . . . . . :
Here you can see that the IP address and subnet masks are set to 0.0.0.0 and the Default Gateway address is blank. When you release an IP lease,
you can’t communicate with the network by using TCPIP until you issue an ipconfig renew
command to renew the IP configuration or restart the computer.
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Part V: TCPIP and the Internet
Part VI
The Part of Tens
In this part . . .
I
f you keep this book in the bathroom, the chapters in this section are the ones that you’ll read most. Each
chapter consists of ten more or less things that are worth knowing about various aspects of networking.
Without further ado, here they are, direct from the home office in sunny Fresno, California.
Chapter 26
Ten Big Network Mistakes
In This Chapter
䊳
Skimping on cable
䊳
Turning off or restarting a server while users are logged on
䊳
Deleting important files that live on the server
䊳
Copying a file from the server, changing it, and then copying it back
䊳
Sending something to the printer again just because it didn’t print the first time
䊳
Unplugging a cable while the computer is on
䊳
Always blaming the network
J
ust about the time you figure out how to avoid the most embarrassing computer mistakes such as using your CD drive’s tray as a cup holder,
the network lands on your computer. Now you have a whole new list of dumb things you can do, mistakes that can give your average computer geek a belly
laugh because they seem so basic to him. Well, that’s because he’s a computer geek. Nobody had to tell him not to fold the floppy disk — he was born with
an extra gene that gave him an instinctive knowledge of such things.
Here’s a list of some of the most common mistakes made by network novices. Avoid these mistakes and you deprive your local computer geek of the plea-
sure of a good laugh at your expense.
Skimping on Cable
If your network consists of more than a few computers or has computers located in different rooms, you should invest in a professional-quality cable
installation, complete with wall-mounted jacks, patch panels, and high- quality hubs. It is tempting to cut costs by using the cheapest hubs and by
stringing inexpensive cable directly from the hubs to each computer on the network. But in the long run, that approach will actually prove to be more
expensive than investing in a good cable installation in the first place.
