Logo
programming4us
programming4us
programming4us
programming4us
Home
programming4us
XP
programming4us
Windows Vista
programming4us
Windows 7
programming4us
Windows Azure
programming4us
Windows Server
programming4us
Windows Phone
 
Windows Vista

Managing Change through Group Policy (part 2) - Working with central policies

- Free product key for windows 10
- Free Product Key for Microsoft office 365
- Malwarebytes Premium 3.7.1 Serial Keys (LifeTime) 2019
7/18/2013 5:59:09 PM

2. Working with central policies

In addition to local Group Policy Objects, networks that run Active Directory have centralized GPOs. Compared to local GPOs, centralized GPOs are management GPOs because you can modify them in a central location and have them affect any group of objects. By default, every AD network includes two default policies:

  • The Default Domain Policy

  • The Default Domain Controller (DC) Policy

A specific default domain policy is applied to every domain in a network. The same applies for the default DC policy, except that instead of being applied at the domain level, this policy is applied specifically to domain controllers. Although these two GPOs have little impact on PCs, they do provide central control elements that affect all users.

The Default Domain Policy is often called the Account Policy because it provides central control of account settings in the network. If your servers are running Windows Server 2003, then you will have only a single account policy. If your servers are running Windows Server 2008, then you can have multiple account policies, all contained within the same GPO. Most organizations use a single account policy and apply it to all users. In some rare cases, organizations use multiple account policies to provide more secure login restrictions for key groups of users, for example, the Administrators group. This lets them use a more open policy for normal users and a more restrictive one for administrative staff. Your base account policy should include the settings listed in Table 9.1 for both the Account Policies and Local Policies sections. Passwords are an important aspect of any security policy and should be enforced in every organization.

Working with PC-related Group Policy Objects

PC-related GPOs do not exist by default; they must be created and customized. As mentioned earlier, a GPO can manage thousands of settings on computers; in fact, in Vista, GPOs include 2,450 settings by default. These settings are divided into different categories as shown in Table 2.

Table 2. Group Policy Object Contents
Managed ObjectDescription
Computer and User SettingsVista includes options that can control both computer (HKEY_LOCAL_MACHINE or HKLM) or user (HKEY_CURRENT_USER or HKCU) registry settings.
ScriptsVista machines can run startup, shutdown, logon, or logoff scripts. Scripts are assigned through GPOs. Startup and shutdown scripts apply to PCs while logon and logoff scripts apply to users.
Folder RedirectionVista machines can automatically protect user data through the use of folder redirection — the automatic move of local folders to remote servers. In addition, redirected data is available to users from any PC in the network. Finally, redirected data is automatically cached locally through offline folder settings so that users can work on the data even if the network connection is lost. In the event of a connection failure, data is re-synchronized as soon as the connection returns.
Software DeliverySoftware installations that are packaged in Windows Installer format can automatically be assigned to either PCs or users through Group Policy Objects.
Security FeaturesAll of Vista's security features can be controlled centrally through GPOs.

GPOs are divided into two major sections. The first includes computer settings and is designed to apply to a PC no matter who logs on or what their user rights are. The second is focused on user settings and is designed to apply to specific users no matter which computer they log on to. Both sections include many of the same settings, but because of their very nature, both also include settings that are not available in the other.

A good practice is to create GPOs for either users or computers and configure them as single-purpose GPOs; that is, as GPOs that are designed to affect only one single type of object. This makes it easier to control and otherwise manage GPOs. Another good practice is to create as few GPOs as possible. The more GPOs you create, the more confusing your system management practices will become.

Group Policy application concepts

Group Policy settings are applied in a specific order. Computer settings are applied first because these settings are applied when the computer starts up. User settings are applied second as users log onto the system. Computers have their own machine account that must be authenticated in the Active Directory domain when they boot up. During this authentication process the Group Policy is applied.

When multiple GPOs are applied to the same object, for example, if multiple GPOs are applied to a PC, they are applied in order of precedence, as shown in Figure 5.

  1. The local GPO or LSP is applied at computer startup.

  2. If available, GPOs that are assigned to a site are applied next.

  3. Domain GPOs are applied after site GPOs.

  4. Organizational unit GPOs are applied last.

  5. If the object (either computer or user) is located within a child OU and the child OU contains an additional GPO, this GPO is applied last.

This process is often called the L-S-D-OU process for the Local-Site-Domain-OU application order. If conflicts arise between policies, the settings in the last policy override all of the others. For example, if you deny access to an item in the Start menu in the domain policy, but it is allowed in an OU policy, the resultant policy will allow access to the menu.

Figure 5. The Group Policy application process

For this reason, understanding some basic Active Directory concepts before you can proceed with GPO assignment and management is important. AD structures are designed to control how objects are managed in a network. These structures include several basic components:

  • Active Directory Forest: The base structure of a directory that contains all of the objects in the network.

  • AD Domain: A container and an account policy boundary. A domain can contain several different object types: printers, user accounts, machine accounts, groups, shared folders, and much more. A forest can contain several domains. Organizations usually create a single production domain which is designed to contain all of their computer and user accounts. Each domain's objects are managed by domain controllers.

  • Site: A local network that contains domain controllers but that is separated from the rest of the network by a wide area network (WAN) connection.

  • Organizational Unit (OU): A container that is located within a domain. OUs are designed to help regroup objects for better management. Domains can contain millions of objects; therefore, using OUs to properly categorize these objects is important. OUs have four purposes:

    • To categorize objects; that is, to regroups objects of one particular type, for example computers

    • To manage objects by applying GPOs to them

    • To delegate object management, for example, taking all of the computers in an OU and assigning their management to a specific group of PC technicians

    • To hide objects by placing them in an OU and controlling its access rights

As mentioned before, there is at least one GPO that is assigned to each domain: the Default Domain Policy. Site GPOs are fairly rare because they apply to groups of objects within a specific remote office and not to others. Instead of using sites, many organizations will choose to apply a GPO for remote office management to a container that will include every remote office. This is why most organizations apply GPOs to Organizational Units because these can span multiple sites.

As you can see, the structure of your AD domain has such an impact on your PC management strategy.

NOTE

In Windows Server 2008, Active Directory is called Active Directory Domain Services (ADDS) because WS08 includes several different technologies which are all labeled with the Active Directory name. Along with Active Directory Domain Services, these include Active Directory Certificate Services, Active Directory Lightweight Directory Services, Active Directory Rights Management Services, and Active Directory Federation Services. However, because the previous two versions of Windows Server, 2000 and 2003, referred to Active Directory as Active Directory alone, most people still refer to ADDS as Active Directory.

Controlling GPO inheritance

In addition to the application order, you can control how GPOs will be inherited from one location to another. Remember that by default, GPOs are assigned through the LSDOU rule. However, if you assign a GPO at the domain level and you want to make sure that its settings are not overridden by GPOs that are assigned after it (GPOs that are assigned to an OU, for example), you can force the application of your settings. You do this by forcing GPO inheritance.

When GPOs are inherited through the LSDOU inheritance order, they automatically override each other if they contain conflicting settings. If settings are applied in a domain GPO, but are removed in an OU GPO, then the OU GPO contains the setting that will be applied. If a setting is applied in a parent OU and then removed in a child OU, then the setting in the child OU will be applied. But, in certain situations, you want to make sure that global policies are not overridden by more focused policies. To do this, you can assign the Enforced attribute to the GPO. Using the Enforced attribute ensures that the GPO will not be overridden by any other.

Conversely, you might want to ensure that certain more focused GPOs are not overridden by global GPOs. You can also do this by assigning a Block Inheritance attribute, but this time, not to the GPO itself, but rather to the Organizational Unit itself.

As you can see, you could assign the Enforced attribute to a GPO while someone else assigns the Block Inheritance attribute to his or her OU. Enforcing and Blocking at the same time could lead to quite a bit of confusion in the overall settings that would be applied, but fear not: Enforced always wins. Despite the fact that Enforced always wins, you should use the Enforced and Block Inheritance attributes sparingly and make sure your overall GPO strategy is coherent and does not require either setting.

Controlling GPO updates

By default, Group Policy Objects are updated on a regular schedule on all systems, PCs and servers. Domain controllers are updated every 5 minutes because they provide an essential service. PCs and member servers are updated at 90-minute intervals. If the contents of a policy have not changed since the last time it was applied, it is not applied again.

Each Group Policy Object includes a file named GPT.INI. This file contains the version number for the GPO. Each time a change is applied to the GPO, this version number is incremented. When the GPO refresh is applied, the system reads the GPT.INI to see if the version number has changed. If it hasn't changed, then there are no updates to the system. If it has, then the system reads the policy and applies any changes.

You can modify the default behavior, once again, through GPO settings.

You can also force the reapplication of GPOs to any system. Do this by using a command line tool:

gpupdate /force

Using this command on any system updates both computer and user GPOs and reapplies all settings even if the version number has not changed.

Structuring GPO application for PCs

Group policy is a very powerful management tool that can be applied to four different object categories:

  • Domain controllers

  • PCs

  • Member servers

  • User accounts

In terms of Vista, you should be concerned about the application of GPO settings to PCs and user accounts. Domain controllers and member servers are under the purview of other administrators in the network. These won't change until your servers are upgraded to Windows Server 2008. At that point, they will benefit from the many features Microsoft has enhanced in Vista. Until then, the only items that can profit from Vista's new GPO settings will be PCs running Vista and the users who have access to them.

NOTE

Group Policy is an excellent vehicle for system administration, but it is possible to overdo it. Begin your Vista GPO strategy by inventorying the GPOs you have in place and then look them over to see if there is room for rationalization. Because Vista brings so many new settings, you don't want to find yourself in a situation where you are proliferating GPOs.

PCs should be further segregated into different categories. Because GPOs are inherited and are mostly applied to organizational units, you should create a hierarchical OU structure that will refine settings as your categories are developed. For example, you should create a main GPO that will affect all PCs whether they are workstations or mobile computers. Then, you should create sub-GPOs that would refine settings based on whether a system is a desktop or a mobile PC. For example, desktops will rarely rely on wireless networks whereas mobile systems will often do so. Desktops will rely on wired communications and may not require communication encryption whereas mobile systems will.

For this strategy to work, you need to create a corresponding OU structure as seen in Figure 6. This structure includes a main OU that will include two sub-OUs. The main OU is named PCs and includes a targeted GPO that contains settings for all PCs. Sub-OUs include desktops and mobile systems. Each sub-OU contains a corresponding GPO to further refine settings. Note that the Desktops GPO is optional since you may not need to further refine settings beyond those applied to all PCs. It is still important to create this OU though in order to categorize desktop systems and separate them from mobile systems.

Figure 6. Creating an OU structure for PC management

A third sub-OU can be used when you have Kiosk PCs or PCs that are exposed to the public and require advanced security settings. These PCs will rely on GPO Loopback settings. Loopback settings always ensure that computer settings are applied no matter who logs on. This is performed in one of two ways. Merged settings will append computer settings once user settings are applied. Replaced settings will completely replace user settings with computer settings. Policy loopback is controlled in the Computer Configuration under Administrative Templates => System => Group Policy.

NOTE

By default, computer accounts created in Active Directory are stored in the Computers container. Similarly, user accounts are stored in the Users container. Both of these containers are special containers that do not behave as OUs and therefore cannot be the target of Group Policy Objects. Because of this, you must create new OUs that will contain PC and user accounts. To make sure that you do not confuse these new OUs with the default containers, call them PCs and People. Then, after these OUs are created, move the PC and user accounts to the appropriate levels in the OU structure to begin their management through GPOs.

In some cases, organizations decide to group PCs on a regional basis because doing this lets them delegate PC administration to regional technicians. In this case, you still need to create the PCs, Desktop and PCs, and Mobile OU structures to differentiate between desktops and mobile systems.

Structuring GPO application for users

Designing policy application for users is a bit more complicated because user GPOs can become quite granular if you're not careful. We recommended that you keep user GPOs to a minimum. In fact, you can often have one single user-oriented GPO and have it apply to all users through the People top-level OU.

You can refine the structure of the People OU by including sub-OUs, but unless you have the need to provide separate management settings for different types of users, there should be no need for other user-oriented GPOs as shown Figure 7.

Follow the keep it simple, stupid (KISS) rule and keep it as simple as possible. Doing this makes it much easier to manage GPO content and will make GPO troubleshooting much more straightforward when required.

Figure 7. The People OU structure and applicable GPOs

Other -----------------
- Securing the Workstation : Applying the Castle Defense System (part 7) - Working with external access - Working with Public Key Infrastructures, Working with Virtual Private Network connections
- Securing the Workstation : Applying the Castle Defense System (part 6) - Working with external access - Working with the Windows Firewall with Advanced Security
- Securing the Workstation : Applying the Castle Defense System (part 5) - Managing information access
- Securing the Workstation : Applying the Castle Defense System (part 4) - Hardening the system - USB Device Control, Windows Defender
- Securing the Workstation : Applying the Castle Defense System (part 3) - Hardening the system - User Account Control
- Securing the Workstation : Applying the Castle Defense System (part 2) - Hardening the system - Local Security Policy and security configurations
- Securing the Workstation : Applying the Castle Defense System (part 1) - Protecting information, Working with protection
- Participating in Internet Newsgroups : Setting News Options - Options for Newsgroups and Messages, Options for Individual Newsgroups
- Participating in Internet Newsgroups : Filtering Newsgroup Messages, Rating Posts
- Participating in Internet Newsgroups : Notes on Working with Newsgroup Messages, Following Up a Message, Posting a New Message
 
 
Top 10
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Finding containers and lists in Visio (part 2) - Wireframes,Legends
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Finding containers and lists in Visio (part 1) - Swimlanes
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Formatting and sizing lists
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Adding shapes to lists
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Sizing containers
- Microsoft Access 2010 : Control Properties and Why to Use Them (part 3) - The Other Properties of a Control
- Microsoft Access 2010 : Control Properties and Why to Use Them (part 2) - The Data Properties of a Control
- Microsoft Access 2010 : Control Properties and Why to Use Them (part 1) - The Format Properties of a Control
- Microsoft Access 2010 : Form Properties and Why Should You Use Them - Working with the Properties Window
- Microsoft Visio 2013 : Using the Organization Chart Wizard with new data
 
programming4us
Windows Vista
programming4us
Windows 7
programming4us
Windows Azure
programming4us
Windows Server