First introduced in Microsoft Windows NT 4.0 as a Service Pack enhancement, the Microsoft Management Console (MMC) is a service that runs within the user mode of Windows NT 4.0, Windows 2000 Professional and Server, and Windows XP Professional and Home Edition. Since its launch in 1999, hundreds of independent software vendors (sometimes called ISVs) have created modules that are used within the MMC framework. Since the introduction of the MMC, Microsoft has included support in the Windows 95 and Windows 98 family of operating systems—in addition to the Windows NT 4.0, Windows 2000, and Windows XP series of operating systems.
Think of the MMC as a common host environment for snap-ins, in which developers can add features not included in the baseline configuration of the operating system. Snap-ins developed by ISVs provide the actual management behavior; MMC itself does not provide any management functionality. The MMC environment provides for seamless integration between snap-ins.
You can create custom management tools from snap-ins as well. Microsoft's direction is to make sure the plug-ins created for handling tasks in Windows NT 4.0 and Windows 2000 also work for Windows XP Professional and Server.
What is MMC?
MMC is a Windows-based multiple documents interface (MDI) application that uses Internet technologies. Both Microsoft and ISVs extend the console by writing MMC snap-ins, which perform management tasks. The MMC programmatic interfaces permit the snap-ins to integrate with the console. These interfaces deal only with user interface extensions—how each snap-in actually performs tasks is entirely up to the snap-in. The relationship of the snap-in to the console consists of sharing a common hosting environment and cross-application integration. The console itself offers no management behavior. Snap-ins always reside in a console; they do not run by themselves. The next section briefly discusses Windows management services and how MMC fits into the management model.
Windows Management Services and MMC
Windows management services are provided as a standard part of the Windows XP operating system. Together, these services act as the management infrastructure, providing a highly scalable foundation on which sophisticated management tools can be built and a base level of common management functions. On top of these services, Microsoft, other software vendors, and corporate developers can layer any number of management tools using the underlying functions of the Windows management services. MMC is a core component in this model.
The Windows Management services are divided into three logical layers:
Common Services. These are the low-level operating system services that form the basis of Windows management services. This layer includes base services such as Active Directory, unified instrumentation, and event notification, to name but a few.
Management Logic. This middle layer has two major areas. The first area consists of the standard management tools that are necessary for change and configuration management, security management, and problem tracking. The second area is the value-added management solutions; that is, the task-based management solutions that both Microsoft and third-party software vendors will provide. The Group Policy MMC snap-in is one of the standard management tools included in the Windows 2000 operating system.
Presentation. This represents the high-level, common services that allow people to tie the other services together and allow people and processes to interact with the services. MMC is part of this layer.
The Windows management services are illustrated in Figure 1.
Figure 1 Windows 2000 and XP management services closely resemble one another.
Figure 2 shows how the Microsoft Management Console works. Clicking Add/Remove Snap-in on the MMC Console menu accesses the Snap-in Manager, which also deals with saving settings into a document (Management Saved Console or .msc file). The items at the top of the picture, the .msc file and the UI elements, are all that a user interacts with. The items at the bottom (the Snap-in Manager, the Routing and Remote Access, and Event Viewer snap-ins) are the elements that the developers interact with.
When an MMC tool is loaded, one or more snap-ins are initialized. These snap-ins are integrated to create the tool's namespace—the hierarchy of objects and containers that are displayed in the console tree; and the details view, which displays the view of a selected item in the console tree. The namespace is a master tree that represents what the tool can do. It appears similar to a tree view of the files and folders on a hard disk. The namespace can include all manageable aspects of a network: computers, users and groups, and so on. The details pane can display information as a list view, Taskpad view, ActiveX control, or an HTML page.
Figure 2 How the Microsoft Management Console works.
The Windows XP Server operating system will include several Active Directory MMC snap-ins: Active Directory Sites and Services, Active Directory Users and Computers, and Active Directory Domains and Trusts. In addition to a standardized location service, the Windows 2000 and Windows XP operating systems include Windows Management Instrumentation (WMI), which provides a uniform model through which management data from any source can be accessed and managed in a standard way.
The Management Logic layer provides two distinct classes of service. It provides standard management tools that are built from the common services; and it enables development of high-end, full function, value-added management solutions. Administrators can maximize users' productivity by using Group Policy—one of the standard Windows XP Server management tools—to ensure that people have the necessary data, applications, operating system, and settings available and optimally configured for their respective job tasks.
Administrators use the Group Policy MMC snap-in to specify options for managed desktop configurations for groups of computers and users. Group Policy provides options for Registry-based policy settings, security settings, software installation, scripts, and folder redirection. The Group Policy settings that administrators create are contained in a Group Policy object (GPO) that is in turn associated with selected Active Directory containers: sites, domains, and Organizational Units (OUs).
Administrators can also set local Group Policy in Windows XP Professional and Server for computers that are not members of a domain. To set local Group Policy, administrators use the Group Policy snap-in focused on the local computer.
Common presentation services such as MMC are also included in the operating system. MMC provides open, extensible, common hosting environment for management applications (snap-ins). MMC provides a unified user interface for hosting administrative tools—including snap-ins—to administer networks, computers, services, and other system components.