Building Your Own Server

When it comes to building a server, many people hesitate. When building a server, there are a lot of choices to make, and equipment is more expensive than equipment for a PC, but the results can be very satisfying.

If you’re considering building your own server, you shouldn’t do it because you intend to save a lot of money – you probably won’t. You often cannot build a PC for less than you’d expect to spend on a major first-tier OEM, such as for a Dell or HP. Components are a commodity, and OEMs buy them by the container load. Best you can hope for is to approach their pricing with your costs. Servers, on the other hand, tend to have higher markups. So it is possible to save some money building your own server. But, again, saving money is not the best reason to build your own server.

The best reason for building your own server is that you can select your own components in a way that buying someone else’s system doesn’t allow for. When you build your own server, you have more control over the setup of the system, and you’re more likely to know what to do or replace when things go wrong. A home-built server is generally rather flexible to configure because you use industry-standard parts and not some proprietary type of casing, memory, or motherboard that will block your upgrade path in the future. Building your own server often results in equipment that has a longer duty cycle because it’s more upgradable.

Building your own server makes sense for another reason: Although system builders make their servers competitvely priced at purchase time, everything else they sell you – from service to upgrade parts and even their shipping – is priced at whatever the market will bear.

Server Purposes and Form Factors

If you have decided to build a server, the first place to start is to determining the intended purpose of the server. That purpose should guide many of your selections. A good rule of thumb when building any system is to try to build a balanced system but oversize that system for any task that is the primary function of the server. A balanced system is one where each subsystem of the server is powerful enough to allow you to avoid bottlenecks. If the purpose of the server is to serve files, then the I/O subsystem needs to be emphasized.

Regarding a balanced system – It’s impossible, or at least too costly, to size subsystems so they never present a bottleneck. When a system gets a job that requires a lot of processing, chances are that the CPU is going to be 100% utilized until the job is near completion. The goal is to allow acceptable performance in those circumstances as well as to maintain a good average CPU utilization rate. That’s one advantage servers offer. If you find that your CPU utilization goes up, if you’ve selected the right motherboard, you can upgrade your processor or add another processor. What typically separates a server from either a workstation or PC is that servers are built with more upgrade options.

Realistically, there are only a few different types of servers that are practical for most people to build themselves:

A basic server, which is really a souped-up PC.
A workgroup server, featuring dual or four-way CPU boards.
An SMB or “Small or Medium Business” server, which is typically a dual-processor system but built with a lower-performing I/O system.

It’s possible to build a thin form factor system using readily available components for rack-mounted units. Two types of servers are difficult to build, given the current retail model:

SMP systems with more than four processors on the motherboard.
Blade systems.

Neither of these two types of system is standardized enough and in great enough demand from the average system builder that companies stock the parts needed to build them. If you intend to build either a large SMP or blade system, you will find yourself spending time talking to the original parts manufacturers themselves. Chances are that for a single board or limited number of boards, they aren’t going to be much help to you.

Server Components

A server should include the following:

Two- or four-way SMP support – It’s a good idea to have at least a two-CPU system, even if you choose to populate just one of the sockets. Having additional CPU sockets allows your system to grow over time.

A high-performance server chipset – The motherboard chipset is of central importance to the overall performance of your system.

Large memory capacity and I/O bandwidth – The amount of memory determines the number of clients you can support, as does your I/O bus.

High-performance network interfaces – Without a strong network interface, you create an unnecessary bottleneck getting data in and out of your server.

Management features – Because a server is supposed to be up and running reliably, it’s important to be able to view what’s happening on the system and make changes both locally and remotely.

A server operating system – You don’t want to limit the number of connections or any other properties of your system because you’ve used a desktop- or workstation-oriented operating system. Your equipment should be selected with the operating system in mind.

The above list represents a checklist for selecting your basic server components. They’re necessary to create a server, but aren’t probably sufficient for most purposes. Servers are differentiated from workstations or desktops through the addition of these features:

Redundant components that allow for graceful failover – Redundant components used are power supplies, fans, and hard drives.

Hot-swappable components – The most important hot-swappable components are disks, but it’s valuable to be able to swap out other components.

High-performance and high-capacity storage – The purpose of your server determines the amount of storage (and memory) that you need.

Intelligent RAID arrays that allow for advanced volume management – RAID arrays make so many important volume operations possible that they are really a requirement for most servers these days.

All these requirements speak to the fundamental differences between workstations/desktops and servers. Servers must be much more dependable, must be higher performing, and must be flexible and have room to grow. Servers require a significantly higher investment than standard PCs, so you want to maximize your investment in them by selecting components that support the features described in the above section.

Assembling a Server

After you’ve selected your components, the next step is to assemble the system. In most respects, there isn’t much difference between assembling a server and assembling a PC. There are, however, a few critical differences, so in the section below, I discuss the construction of a hypothetical server, step-by-step.

Installing Core Components

First, let’s take a walk through the casing assembly, assuming you bought a case with no pre-assembled components already installed. Begin as following:

1. On a good work surface with adequate lighting, open the case and remove any included screws, mounting brackets, disk cages, and other components that you will be populating with parts.

2. Take a good look at your case to familarize yourself with the design and determine some fundamental issues, such as power supply placement, and number of fans needed and what type.

3. Install the power supply, and don’t skimp on it. Your power supply should be sufficient to run all your components well below the stated operating limit and should have good thermal properties as well as run quietly. You can pay a lot for a server power supply, but it’s money well spent.

4. Install all the fans. The goal of cooling your system should be to create airflow through the case so that it dissipates heat. A lot of system builders position their fans so that intake is from the front of the case, and exhaust is out the back. Some units, such as drive cages, may require their own fans.

5. Install the motherboard as well as any backplane your system may have.

6. Install your CPU and then attach your cooler or heat sink and plug it into your motherboard’s CPU connector. Be sure to either use an ESD wrist strap to prevent electrostatic discharge or ground yourself properly.

7. Attach your case’s front panel connections (power, power LED, restart, HD LED and speaker) to the motherboard’s connectors. Visually inspect the connections up close to verify they’re on the correct posts and the polarities are correct.

8. Insert one stick of RAM into your system, on the slot closest to the CPU.

9. If your motherboard doesn’t have a video chipset built in, install your video card into the appropriate slot: AGP, PCI-x, etc.

10. Attach a keyboard, video monitor and mouse or attach the appropriate leads to your KVM switch.

11. Boot up your system, verify it proceeds to the BIOS, and stops at the point it can’t find a boot device.

It’s a good idea to test the basic system at step 11, because it becomes increasingly difficult to diagnose problems later on, when there are more potential causes. At this point, if there are issues, you can swap the memory, change RAM slots, swapping the CPU or video board, changing the power supply, and checking your connections. In your initial boot to the BIOS, you can determine whether your power LED is functioning, whether your restart button works, and whether you’re getting beep sounds.

Installing the Remaining Components

After you’ve installed the core components, you can add your peripheral  devices. It’s a good general rule to add 2-3 devices at a time and then test the boot process to ensure the additions aren’t causing problems.  Below are some steps you need to follow, but the order isn’t as important as the previous list:

1. Add the remaining memory. Be sure to test your system again once all modules are installed to check for any potential problems.

2. (Optional) Install your floppy drive. Be sure the red wire in the connection is closest to the floppy power connector (not all floppy drives have this requirement).

3. Install any optical drives and connect the ATA/IDE, SATA or USB connection, the audio connection and the power connection to it.

4. In you’re installing a USB flash storage reader or any other USB storage device, install it, but do not connect it to your USB bus. The reason you don’t want to do this is to avoid your operating system from grabbing a set of drive labels for these devices until you’re done assigning devices to your more common drives.

5. Install any PCI, PCI-x or PCI-Express boards into their correct slots and connect any supported devices (such as hard drives) to those boards.

6. Test your system to make sure all devices are recognized and renumerated by the BIOS.

At this point, your server is fully populated and ready for configuration. If you’re using hardware RAID, you’ll need to follow the steps below:

1. During the boot process, go into the RAID BIOS and create the RAID container.

2. Add all the drives you intend to use in your array and designate any additional drives that you want to keep as spares.

3. After you create the container, use the RAID BIOS to create the hardware RAID type: RAID 5, RAID 1+0 and so on.

The process of creating the container is fast, but striping a large array can take some time.

Installing an Operating System

After your RAID has been configured, it’s time to install your operating system and complete the installation. To install your operating system, follow the steps below:

1. Insert the O/S install disc into your optical drive and start your system.

2. As your system proceeds past the BIOS and into the installation routine, make sure to correctly specify what your boot device will be and that you have the correct driver in hand to install so that your operating system will recognize the device.

In many instances, an operating system may come with the correct driver, but whenever possible, you should try to install the very latest driver from the vendor’s Website. If you are installing a RAID system, try to have that driver on hand for your operating system.

3. As part of the installation routine, specify the boot partition and the type of drive formatting you wish to have on it. With Windows Server, you probably want NTFS; with Linux or Unix, you may need to specify not only the partition and its type but also the number and definitions of any slices on the drive. Formatting a large volume takes some time, so this is a good time to attend to other tasks.

4. Proceed through the installation, specifying the details of your network connections as well as the particular system components that you want to install.

5. When your operating system is installed, shut down the system and connect your USB connections for any USB drives.

In building a server, the steps people seems to have trouble with are creating the RAID container and not having the correct device driver in hand. Many RAID boards are poorly documented, and if you haven’t done a system build before, you might not realize that you need to create a container first and stripe it prior to installing the operating system and then formatting the volume. The container and its striping are a hardware feature, separate from the formatting the operating system does.

With your server now up and running, it’s good practice to let it burn for 48 hours, monitoring your system temperature, which can be done using capabilities built into modern motherboards. In particular, you should monitor your CPU temperature to verify it’s not overheating.

Command Line Backup & Restore Using reg.exe

A command line registry manipulation tool called reg.exe is included with Windows XP. This tool is useful for selectively backing up or restoring specific Registry subkeys. Numerous functions are available in reg.exe, including Registry exporting and importing.

To backup a Registry key using reg.exe, use the following syntax:

reg export rootkey\subkey filename

For rootkey, you can use the abbreviations HKLM, HKCU, HKCR, HKU or HKCC. Subkey must be the full name of a Registry key under the selected root. Filename is the name of the file to which you want to save the exported data.

To restore a Registry key using reg, use the following syntax:

reg import filename

When importing, filename can be any file created by reg export, from the regedit Registry Editor’s Export command, or created manually with a text editor.

Server Categories

Entry-Level Servers - An entry-level server is a one- or two-processor system meant to provide a network service or services to as few as one client/user, up to as many as a workgroup. Many entry-level servers are used in horizontally deployed applications.

Midrange Servers – The midrange server offerings are viewed as department-level servers or servers that can provide network services to 10 clients/users, up to 250 clients/users for large applications. For simpler network services, such as DNS, a server of this class might service thousands of users.

Enterprise Servers – An enterprise server is a PC-based server equivalent of a mainframe. Sun’s systems in this area scale to hundreds of processors and are used for applications such as databases that best scale vertically.

Blade Servers – A blade server is a motherboard that’s been modified so it fits into a chassis and is hot-swappable.

Appliances – An appliance server is a special-purpose server that requires little maintenance and/or management.

Carrier-Grade Servers – This line of servers offers NEBS Level 3 (Network Equipment Building System, an industry standard) solutions for the telecommunications industry and for back offices.

Storage Servers – Sun is a major supplier of storage arrays, tape backup systems, and storage software, through its StorEdge line. Sun’s business is mostly to Sun server customers, but it also plays a central role as a management console of choice for Storage Area Networks (SANs).

Wildcards With the DIR Command

Visualize having 273 files in one directory. A few of those files have their extension .doc, but most don’t. You’re only looking for files with the .doc extension. Wouldn’t it be nice to type the DIR command so that only the .doc files come up? You can do this using wildcards.

A wildcard is one of two special characters, asterisk (*) and question mark (?), that can be used in place of all or part of a filename, often to enable a command-line command to act on more than one file at a time. Wildcards work with all command-line commands that take filenames. A great example is the DIR command. When you execute a plain DIR command, it finds and displays all the files and folders in the specified directory; however, you can also narrow its search by adding a filename.

If you want to confirm the presence of a particular file in a particular place, this is very convenient. But suppose you want to see all files with the extension .txt. In that case, you use the * wildcard, like this: dir *.txt. A good way to think of the * wildcard is “I don’t care.” Replace the part of the filename that you don’t care about with an asterisk.

Wildcards also substitute for parts of filenames. This DIR command will find every file that starts with the letter a:

C:\>dir a*.*

We’ve used wildcards only with the DIR command, but virtually every command that deals with files will take wildcards.

Installing DNS on a Windows Server

Windows clients in the network use DNS to locate domain controllers, which hold the Active Directory database. When you decide to promote a Windows Server to become a domain controller, you’ll be prompted to install a DNS server as well, unless another DNS server already exists on the network. After the domain controller has been properly configured, it will register records in DNS that enable clients to find the domain controllers in the domain.

However, you can always install a DNS server on Windows Server whether or not you decide to use the Active Directory. For example, you might have a few Windows servers in a Unix network and decide to use Microsoft’s version of DNS because you find the graphical interface easy to use. Or you might want to install additional DNS servers to provide a backup for a primary DNS server. You don’t have to install the DNS service on just a domain controller, but the system must run Windows 2000 Server or Windows Server 2003.

Installing the service is just as simple as installing the WINS service:

1. Click Start, Programs, Control Panel (Start/Control Panel for Windows Server 2003).
2. From the Control Panel, double-click the Add/Remove Programs icon.
3. When the Add/Remove Programs window pops up, click Add/Remove Windows Components (on the left part of the window). The Add/Remove Programs window now displays a Components button in the upper-right side of the window. Click the Components button, and the Windows Components Wizard dialog box pops up.
4. Scroll down until you find Networking Services and highlight it by clicking it once. Then click the Details button.
5. When the Networking Services dialog box appears, scroll down until you find Domain Name System (DNS). Click the check box next to the component and click OK.
6. When prompted, insert the Windows Server source CD into your CD-ROM drive and then wait a minute or so until while files are copied to your hard drive. When the Windows Components Wizard window reappears, click Next.
7. Another window appears, titled Completing the Windows Components Wizard. Click Finish.
8. When the Add/Remove Programs window reappears, click OK or Close.

Steps for Configuring TCP/IP

By default, the TCP/IP protocol is configured to receive its IP information (IP address, subnet mask, etc.) automatically from a Dynamic Host Configuration Protocol (DHCP) server on the network. Anyway, here’s how it’s done manually:

1. In Windows XP, open the Control Panel and double-click the Network Connections applet. Double-click the Local Area Connection icon. In Windows 2000, click Start> Settings> Network and Dial-Up Connections, and double-click the Local Area Connection icon. In Windows 9x/Me, alternate-click Network Neighborhood and double-click My Network Places to to get to your network settings.

2. Click Properties, highlight the Internet protocol (TCP/IP), and click Properties.

3. In the dialog box, click the Use the Following IP Address radio button.

4. Enter the IP address in the appropriate fields.

5. Press the TAB key to skip down to the subnet mask fields. Note that the subnet mask is entered automatically (this can be overwritten to enter a different subnet mask).

6. Optionally, enter the IP address for a default gateway (router or another computer system that will forward transmissions beyond your network).

7. Optionally, enter the IP address of a primary and secondary DNS server.

8. Click OK to close the dialog box.

9. Click Close to exit the Local Area Connection Status dialog box.

10. Windows will alert you that you must restart the for the changes to take effect.

Access Control Lists

Access Control Lists (ACL) are used by routers and other networking devices to control traffic that comes in and out of your network. These access lists can be general in nature or specific to certain types of communications. Access Lists are typically used in firewalls to control communications between public and private networks, but they can also be used on internal routers to regulate traffic within the network. An Access List Entry (ALE), which is contained inside the ACL, usually includes where the network packet is coming from, where it’s going, what the protocol is (whether TCP or UDP), the TCP/IP port it uses, and, finally, whether access is allowed or denied. The types of parameters that can be controlled using an access list include the following:

Source Address – This parameter specifies the originating source IP address of a packet. The source address can be an internal or external machine, or an internal address that it proxies to an external address.

Destination Address – The destination IP address specifies where the packet is going. This can be internal or external to the network.

Port Numbers – This parameter specifies the TCP/IP port number the communication is using. Each type of  TCP/IP service uses a standard port.

Protocol – This parameter identifies the protocol being used in the transmission, such as File Transfer Protocol (FTP), Hypertext Transfer Protocol (HTTP), or Dynamic Host Configuration Protocol (DHCP). This is usually used in conjunction with a port number that’s standard to that protocol or service. This parameter can also be used to define whether the protocol is using TCP or UDP.

Permit or Deny – This parameter is used to permit or deny the communication specified in the access list entry.

The following is an example of an ACL entry for a router:

L 8-1        permit source 192.168.13.2 destination 10.1.5.25 tcp port 80

The syntax used by your router or network device will be similar to this entry, but it varies from vendor to vendor. ACLs can be a valuable security tool for locking down access to certain networks or hosts. This type of access control is critical for preventing spoofing attacks, where an unauthorized user tries to masquerade their external host as an internal system by spoofing the IP address to look like it’s coming from the internal network. An ACL can be set up to prevent external traffic coming in as an internal address.

Virtual Memory & Page File Settings

Windows Virtual Memory system works  by writing data that won’t fit into RAM into a page file that holds the overflow. For efficient operation, the page file should be unfragmentedand positioned either on its own physical disk drive (preferably a disk that’s seldom used), or on the Windows disk but not on a drive that’s really just an alternate partition on the same physical drive as the Windows installation drive.

To configure Page File sizes and locations, you must be logged on as a Computer Administrator. Right-click My Computer and select Properties to open the System Properties dialog. Select the Advanced tab, and click the top Settings button under Performance. Select the Advanced tab and click the Change button under Virtual Memory.

After first installing Windows, there will probably be a page file located on drive C: (or the boot drive) with the System Managed Size option selected. You can create page files on more appropriate, faster drives and leave the original file as is, or delete it.

To create a new page file, select a drive letter in the upper part of the dialog and select either Custom Size or System Managed Size. If you want to prevent the page file from fragmenting, create it on a freshly formatted or defragmented drive or and set a custom initial size at 1.5 to 3 times the amount of physical RAM installed in your computer. To prevent the page file from growing or fragmenting, set its maximum size at the same amount. The new file will be created and used immediately.

If you are not sure what your system’s memory demands will be, leave the page file set to System Managed Size and let Windows manage it.

To delete a page file, select a drive letter in the upper-hand part of the dialog and select No Paging File. The file will be freed and deleted when you restart Windows.

Tools for Maintaining & Optimizing Windows

For years, techs have accepted as their lot in life the curse of having to use dozens of different command line and GUI tools that simply did not behave in a consistent way. Microsoft addresses this issue in Windows 2000 and XP with the Microsoft Management Console (MMC). The MCC enables Microsoft, and third-party vendors, to create tools that present a consistent face while maintaining a high degree of flexibility.

Another tool that is built into Windows 2000/XP is the Task Manager. The Task Manager enables you to monitor currently running programs and processes, change their priority, and stop them if necessary.

Microsoft Management Console (MMC)
The MMC is simply a shell program that holds individual utilities called snap-ins. You can start the MMC by opening the Run option and typing in MMC to get a blank MMC console. Blank MMC consoles aren’t much to look at. The function of the MMC changes depending on what snap-in is loaded. Many of the tools in the Control Panel’s Administrative Tools folder are simply pre-configured MMC’s. Virtually every traditional windows tool – and a lot of new ones – are now snap-ins. You can easily create custom MMC’s with the snap-ins of your choice loaded. Let’s look at how to do that by manually loading one of your most important tools, the Device Manager.

Device Manager
As you know, the Device Manager is one of the most used tools we have (it’s oddly not included with Windows NT). It’s easy enough to get to it the traditional way – by opening the System Properties applet in the Control Panel, clicking the Hardware tab, and then clicking the Device Manager button – but it makes more sense to “cut to the chase” and configure a custom MMC with the Device Manager. Open up a blank MMC, then in Windows 2000, click Console; in Windows XP, click File. In either O/S, select Add/Remove Snap-in, and then click the Add button to see a list of available snap-ins. After you click Add, choose the computer the snap-in will manage. Select Local Computer to focus on the local system, or browse to always focus the tool on a different computer on your network, and click Finish. After this, close the Add Standalone Snap-in box. The Device Manager will be listed in the Standalone page of the Add/Remove Snap-in box. Click OK to close it, and then click Device Manager under Console Root. Once you’ve added the snap-in you want, just save the console under any name you want (with the extension of .msc). Now, you’re only a double-click away from the Device Manager! Microsoft also knows that some folks like things the old way, so the company has created a bunch of pre-made, locked consoles for you and dropped them in the same places, where you’d expect them to be (if you have previous experience with Windows 9x). You can open the Windows System Utility in Windows 2000/XP, for example, by clicking Start/Programs/Accessories/System Tools/System Information. It’s the good ol’ System Information Utility, but it’s an MMC-style snap-in.

Event Viewer
Another important snap-in is Windows Event Viewer. Work with Event Viewer (available in Windows NT, 2000 and XP). Work with Event Viewer for a while and you’ll see that monitoring various log files reveals things about the health of the operating system through the behavior (logged events) of its services and applications. Event Viewer is usually started from the Administrative Tools. In Windows 2000, open the Control Panel, double-click the Administrative Tools icon, and double-click the Event Viewer icon. In Windows XP, open the Control Panel, double-click the Performance and Maintenance icon, then Administrative Tools, then Event Viewer. The Event Viewer will display events from three log files: Application, Security and System. 

Types of Events
Event Viewer displays five types of events. The System and Applications logs have Error, Warning, and Information events, while the Security log displays Success Audit and Failure Audit events. An Error event is bad news – something’s broken or data has been lost. In the Application log, this can mean an entire application hung up or an operation failed. In the System log, this can mean that a service failed. A service is a special program that provides specific functionality to the O/S. A warning is something that isn’t critical, but may mean there is trouble to come. For instance, if disk space is low, a Warning event is logged. An information event is the only good news, because it means an application, driver, or service successfully completed an operation.

Event Viewer Settings
In Event Viewer, alternate-click System select Properties. In Properties, look at the Log Size box, which defines the maximum size a log file may grow to, and what action should be taken when the log file reaches the maximum. The defaults are 512 KB and Overwrite Events Older Than 7 Days. You can easily reconfigure these settings, but be aware that large log files take up a lot of space on the hard disk drive. If scrolling through large log files makes you dizzy, you can use Filter settings to make the viewer show only specific selections. Change the filter settings so that when you are viewing a large log file, you can filter out events by type, source, category ID, user, computer, and date. Keep in mind that this controls only what Event Viewer displays: all events will still be logged to the file, so you can change your filter settings without worrying about losing logged data.

Clearing, Archiving and Opening a Log File
Clear the System Log by alternate-clicking System Log and selecting Clear All Events. You’ll be prompted to save the System Log. To do so, click the Yes button. You can archive a log file that you want to be able to view later by saving it with a unique filename. To open the file you just saved, click the Action menu, select Open Log File, select the file, then the log type (System, Application, or Security), and then click Open.

Task Manager
The Task Manager is another important utility in the tech’s toolbox. Not an MMC snap-in, but a freestanding utility, the Task Manager enables you to monitor, in real time, your PC’s currently running programs and processes and gauge overall system performance. There are several ways to look at the Task Manager. The following work in Windows NT, 2000 and XP:

Press the CTRL-SHIFT-ESC key combination
Press CTRL-ALT-DEL once
Alternate click on a blank area of the task bar and select Task Manager from the pop-up menu
Select Start | Run and type taskmgr

The Task Manager displays three property sheets: Applications, Processes, and Performance. Windows XP also adds tabs for Networking and Users. At the bottom of the utility window is a summary of the total number of processes running, total CPU usage, and total RAM usage (called Commit Charge in Windows XP).

Applications
The Applications property sheet shows all applications currently running on your system, along with their active status (Running, Not Responding, or Stopped). Using the Application property sheet,  you can close an application (End Task), make an application active (Switch To), or start an application (New Task).

Processes
Every program or service running on your system is actually one or more discrete process. The Processes property sheet lists processes and services currently running on the system. There’s a lot you can do from the Processes tab. Look at the Processes tab on your system and compare it to the Application tab. Notice that there’s a lot of stuff showing in process that doesn’t show applications.That’s because the Applications tab shows only applications started by the user. It does not show any services or any child processes started by applications or by services. You can end a process in the Processes tab by alternate clicking and selecting End Task from the pop-up menu. The End Process Tree will close that process and any other processes started by that process. Notepad is a simple program that does not start any other processes, so just click End Process – Windows gives you a warning screen – then click OK. You can do a lot more than just close processes in the Processes tab. For each process running, you will see a unique Process ID (PID), the amount of CPU time that the process is using, the amount of time the process has been running, and the amount of system memory usage. One of the handiest aspects of the Process tab is the memory usage. Try starting a few bigger programs – Microsoft Word is a good example – and see how much memory they use.  You can also set the priority for processes in the Process tab – a very handy way to give more important programs more of the CPU’s time. the priority determines the order in which the threads of a process are scheduled for the CPU. To set a base priority for a process, alternate click the process and select Set Priority from the pop-up menu, then select a base priority for the process to run at. Choices are Real-Time, High, Above Normal, Normal, Below Normal, and Low. Be aware that increasing the base priority of one process may adversely affect other processes running on the system. This is especially so if you assign a process Realtime base priority, which, depending on the application, can cause the system to stop responding.

Performance
The Performance property sheet gives you a graphical overview of the system’s CPU and memory usage. You can see real-time graphs of CPU and memory usage and the total number of handles, threads  and other processes.

Handles are values assigned to open resources such as files or Registry keys. Threads are discrete chunks of processes. Just as a program is made of processes, a process is made of threads.

The Performance tab gives some very nice details on memory usage, particularly the physical, commit charge, and kernel memory statistics.

Physical memory is the actual RAM on your system. The Performance tab shows the total amount of RAM, the amount available, and the amount used for the system cache (the system cache is basically just the disk  cache).

Commit Charge memory is the amount of memory that is actually being used. The Limit is the total amount of both physical and virtual memory, and the Peak is the most you have used recently.

Kernel Memory statistics show the memory used by the core Windows files. This one is probably the least useful.

Networking
Available only on Windows XP, the Networking tab shows the State, Link, Speed and Percentage of Network Utilization for NICs installed on the system. Aside from providing a pretty graph, the Networking tab doesn’t enable you to perform any real technical tasks on your NIC or network connection.

Users
The Users tab shows names and session status of users configured to access the PC. You can use this tab to disconnect users currently logged onto the system, or send messages to users on other systems in the same workgroup. The Users tab is available on Windows XP PCs that belong to a workgroup (no domain) and have Fast User Switching enabled.

Troubleshooting a VPN Connection

If you are unable to connect to a VPN server, check the following:

Check basic settings such as username, password and host name or IP address. These settings are easy to change, and a single digit or letter error is enough to prevent a successful connection.

Compare the settings used by your VPN client to those expected by the VPN server. Adjust client settings to match those used by the server.

If you use a router to connect your computer to the Internet, make sure the router is configured to provide IPSec and PPTP pass-through. With a Linksys router, check the filters dialog to check these settings. For other routers, check your documentation. If either or both pass-through settings are disabled, you are not able to connect to a VPN server.

If you use a router to connect your computer to the Internet and another user has a VPN connection running, but you can’t connect at the same time, this is normal. Most low-cost routers for home and small office support IPSec and PPTP pass-through for only one user at a time.