Configuring Password and Lockout Policies in Windows Server 2008

In a Windows Server 2008 domain, users are required to change their password every 42 days, and a password must be at least seven characters long and meet complexity requirements including the use of three of four character types: uppercase, lowercase, numeric, and nonalphanumeric.

Use the buttons below to navigate through the lesson

Three password policies—maximum password age, password length, and password complexity—are among the first policies encountered by administrators and users alike in an Active Directory domain. Rarely do these default settings align precisely with the password security requirements of an organization. Your organization might require passwords to be changed more or less frequently or to be longer.

There are exceptions to every rule, and you likely have exceptions to your password policies.
To enhance the security of your domain, you can set more restrictive password requirements for accounts assigned to administrators, for accounts used by services such as Microsoft SQL Server, or for a backup utility. In earlier versions of Windows, this was not possible; a single password policy applied to all accounts in the domain.In this lesson, you will learn to configure fine-grained password policies, a new feature in Windows Server 2008 that enables you to assign different password policies to users and groups in your domain.

If the new password meets requirements, Active Directory puts the password through a mathematical algorithm that produces a representation of the password called the hash code. The hash code is unique; no two passwords can create the same hash code. The algorithm used to create the hash code is called a one-way function. You cannot put the hash code through a reverse function to derive the password. The fact that a hash code, and not the password itself, is stored in Active Directory helps increase the security of the user account.

The password settings configured in the Default Domain Policy affect all user accounts in the domain. The settings can be overridden, however, by the password-related properties of the individual user accounts. On the Account tab of a user’s Properties dialog box, you can specify settings such as Password Never Expires or Store Passwords Using Reversible Encryption. For example, if five users have an application that requires direct access to their passwords, you can configure the accounts for those users to store their passwords, using reversible encryption.

In this lesson, you will learn how to implement your enterprise’s password and lockout policies by modifying the Default Domain Policy Group Policy object (GPO).

Click Group Policy Management. Expand the domain. Right Click Default Domain policy and click Edit. Expand – Computer Configuration>Policies>Windows Settings>Security Settings. Expand Account Policies. Select Password Policies. Right Click Maximum password age and select Properties. Change Password will expire in: to 30 days. Click OK. Maximum password age is now set to 30 days. Next select Account lockout policy and right click Account lockout threshold and select Properties. Set invalid logon attempts to 3. When you Click OK Windows will suggest values for the remaining policies, Click OK to accept these. The suggested values can be changed later. Click OK. The Account lockout policy is now configured. All open dialogue boxes can now be closed.

Fine-Grained Password and Lockout Policy

You can also override the domain password and lockout policy by using a new feature of Windows Server 2008 called fine-grained password and lockout policy, often shortened to simply fine-grained password policy.
Fine-grained password policy enables you to configure a policy that applies to one or more groups or users in your domain. To use fine-grained password policy, your domain must be at the Windows Server 2008 domain functional level. To raise the domain functional level open Active Directory Users and Computers.

Right click the domain and select Raise domain functional level. Select Windows Server 2008 and click Raise. Warning Raising the domain functional level cannot be reversed. Click OK to continue. Click Close to complete.

Fine-Grained Password and Lockout Policy

The settings managed by fine-grained password policy are identical to those in the Password Policy and Accounts Policy nodes of a GPO.
However, fine-grained password policies are not implemented as part of Group Policy, nor are they applied as part of a GPO. Instead, there is a separate class of object in Active Directory that maintains the settings for fine-grained password policy: the password settings object (PSO).

Most Active Directory objects can be managed with user-friendly graphical user interface (GUI) tools such as the Active Directory Users and Computers snap-in. You manage PSOs, however, with low-level tools, including ADSI Edit.

In this exercise, you will create a PSO that applies a restrictive, fine-grained password policy to users in the Domain Admins group. Before you proceed with this exercise, confirm that the Domain Admins group is in the Users container. If it is not, move it to the Users container.

Click Administrative tools>ADSI Edit. Expand the domain. Expand CN=System. Select CN=Password Settings Container. Right click and select New>Object. Click Next to continue. Type a name for the new object and click Next.

PSO Precedence and Resultant PSO

A PSO (Password Settings Object) can be linked to more than one group or user, an individual group or user can have more than one PSO linked to it, and a user can belong to multiple groups. So which fine grained password and lockout policy settings apply to a user? One and only one PSO determines the password and lockout settings for a user; this PSO is called the resultant PSO. Each PSO has an attribute that determines the precedence of the PSO. The precedence value is any number greater than 0, where the number 1 indicates highest precedence. If multiple PSOs apply to a user, the PSO with the highest precedence (closest to 1) takes effect.

Set the Precedence value to 1 and click Next. Type False The password is not stored using reversible encryption and click Next. Type 30 The user cannot reuse any of the last 30 passwords and click Next. Type True Password complexity rules are enforced and click Next. Type 10 Password must be at least 10 characters in length and click Next. Type 1:00:00:00. A user cannot change his or her password within one day of a previous change. The format is d:hh:mm:ss (days, hours, minutes, seconds) and click Next. Type 45:00:00:00. The password must be changed every 45 days and click Next. Type 5. Five invalid logons within the time frame specified by (the next attribute) will result in account lockout and click Next. Type 0:01:00:00. Five invalid logons (specified by the previous attribute) within one hour will result in account lockout and click Next. Type 0:01:00:00. An account, if locked out, will remain locked for one hour or until it is unlocked manually. A value of zero will result in the account remaining locked out until an administrator unlocks it and click Next. The attributes listed are required. After clicking Next on the msDS-LockoutDuration attribute page, you will be able to configure the optional attribute. Click the More Attributes button.

In the Edit Attributes box, type CN=DomainAdmins,CN=Users,DC=es-net,DC=co,DC=uk
and click Set. Click OK. The new PSO is now active.

Resultant PSO

To identify the PSO that controls the password and lockout policies for an individual user.

  1. Open the Active Directory Users And Computers snap-in.
  2. Click the View menu and make sure that Advanced Features is selected.
  3. Expand the domain and click the Users container in the console tree.
  4. Right-click the Administrator account and choose Properties.
  5. Click the Attribute Editor tab.
  6. Click the Filter button and make sure that Constructed is selected. The attribute you will locate in the next step is a constructed attribute, meaning that the resultant PSO is not a hard-coded attribute of a user; rather, it is calculated by examining the PSOs linked to a user in real time.
  7. In the Attributes list, locate msDS-ResultantPSO.
  8. Identify the PSO that affects the user.

The Domain Admins PSO that you created is the resultant PSO for the Administrator account.