Sams Teach Yourself MCSE Windows NT Server 4 in 14 Days
(Publisher: Macmillan Computer Publishing)
Author(s): David Schaer, et al
ISBN: 0672311283
Publication Date: 12/15/97

Chapter 4
Configuring the Environment

by David Schaer and Theresa Hadden

4.1. Overview

This chapter will familiarize you with how to configure the most common services and drivers used in Windows NT 4 and the role the registry plays in configuring your environment. Understanding the registry is a required element in understanding how services and applications are implemented in NT Server.

Think of services as applications that perform certain duties. For example, the Alerter service is used to generate notification of significant system events.

A restaurant has waiters and cooks, and although each performs a specific service, one is dependent on the other. If the cooks don’t prepare something to eat, the waiters will have nothing to serve. The waiters are dependent on the cooks. In a similar fashion some of the NT services are dependent on other services that must be running for them to perform their functions.

On the other hand, the registry, which records how these services are configured, is one of the most complicated areas of the NT operating system. Fortunately, when the registry is broken down into a few basic components, the veil is lifted and the overall structure becomes rather simple. The exam focuses on the areas listed in the following MCSE QuickFACTS.

4.1.1. Objectives

The information in this chapter is provided mainly as a basis for properly understanding how to configure services and the use of the registry. This chapter addresses how to

•  Configure Windows NT Server core services

•  Use the registry editor to configure your computer

•  Configure peripherals and devices

•  Choose the appropriate course of action to take to resolve configuration errors

4.1.2. Fast Facts

The following list of facts is a concise picture of the information presented in this chapter. It acts as both an overview for the chapter and as a study aid to help you do any last-minute cramming.

•  Services can run with permissions independent of the logged-on user.

•  A user does not need to be logged on for services to be running.

•  Services can be controlled through Service in the Control Panel, Server Manager, or from the command line with the Net Start command.

•  A service can be set as disabled, manual, or automatic.

•  REGEDT32.EXE or REGEDIT.EXE can be used to modify the registry.

•  By default, only members of the administrators group are assigned permissions to modify the registry.

•  The LastKnownGood control set is located in HKEY_LOCAL_MACHINE.

•  Service parameters are stored in the registry HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services.

•  The SAM and SECURITY hives cannot be modified directly.

•  Changes to HKEY_LOCAL_MACHINE affect all users of the system.

•  If a series of services fails to start it is normally because of the failure of a service on which they depend.

•  The Workstation service is independent of the Server service.

•  The Alerter service generates alert messages; the Messenger service delivers messages.

•  The Server Manager is used to configure alerts.

•  The AT.EXE and WINAT.EXE applets are dependent on the Schedule service.

•  The Netlogon service synchronizes the SAM database between the PDC and BDCs.

•  If the Netlogon service is paused at the PDC, synchronization will continue to be performed.

•  Pausing the Server service does not disconnect currently attached users.

•  Tape drivers are installed through the Tape Devices applet in Control Panel.

•  The UPS service can monitor a UPS with a serial cable attached to a COM port.

•  Changing a driver, such as the mouse driver, affects all users of the system.

•  If a driver or service has been configured improperly, the LastKnownGood control set can be used to return to the previous settings.

•  The right to log on as a service is granted through User Manager for Domains.

•  Service accounts should not be required to change their password.

•  A service that has been paused can be continued.

•  Errors that occur when a service starts will be recorded in the Event Viewer.

•  The LastKnownGood control set is created when you log on.

•  The HARDWARE key is a volatile key that contains the hardware information provided by NTDETECT.COM on x86-based machines.

•  Modify the registry directly only if no applet exists that can make the changes for you.

•  To prevent mistakenly modifying a parameter you can put REGEDT32.EXE in read-only mode.

•  The REGEDT32.EXE Find Key feature, located under Tools, can search only for keys and subkeys; REGEDIT.EXE, however, can also search for values.

•  To back up the registry you must select at least one file on the drive that contains the registry.

4.2. Services Versus Applications

A service is different from an application in many respects. The user always interfaces directly with applications, such as a word processor, but this is not true of all services. Applications are dependent on the logged-on user; when the user logs off, the applications are closed. Services can be active with or without a user logged on to the system.

Services can act independently of the user account that is logged on. The capability to let a service run under a separate account enables the service to perform its operations even if they exceed the rights granted to the logged-on user. Figure 4.1 shows the Directory Replicator configured to start automatically using the rights of the user account DRservice.

Figure 4.1.  The Directory Replicator using the DRservice account.

To quickly see which services are active on a system, type Net Start at the command prompt.

The user account that a service logs on as can be from the local SAM database, the SAM database from the local domain, or the SAM database of a trusted domain. The SRVANY.EXE utility included with the NT 4.0 Resource Kit enables any application to run as a service.