2. Configuring fine-grained password policies
In Windows Server 2003 and earlier, you could have only a single
password policy and account lockout policy governing all user accounts
in a domain. This password policy could be configured by editing the
Default Domain Policy Group Policy Object (GPO)—specifically, the six
policy settings found under
Computer Configuration\Policies\Windows
Settings\Security Settings\Account Policies\Password
Policy
Each domain also had three account lockout policy settings
found under
Computer Configuration\Policies\Windows
Settings\Security Settings\Account Policies\Account Lockout
Policy
Windows Server 2008 introduced a new feature called
fine-grained password policies that you could use
to configure multiple password policies and account lockout policies
for each domain. This provided Active Directory administrators with
greater flexibility because they could create different policies for
different groups of users. The problem, however, was that you needed
to use ADSI Edit and LDIFDE to create fine-grained password policies
on the earlier platform. This task is simplified in Windows Server
2012 because now you can use the GUI-based ADAC for creating
fine-grained password policies. In addition, you can use ADAC to view
the resultant password settings for particular users in your
environment to ensure fine-grained password policies have been
configured as intended.
Understanding fine-grained password policies
Fine-grained password policies can be assigned to users or
groups. If a user belongs to more than one group that has a
fine-grained password policy assigned to it, the precedence value of
each policy is used to determine which policy applies to members of
the group. The precedence value of a policy must be an integer value
of 1 or greater. If multiple policies apply to the same user, the
policy having the lowest precedence value wins.
Note
REAL WORLD Understanding
policy preference
Consider a scenario where a user named Karen Berg in the
corp.contoso.com domain is a member of two groups: the Marketing
group and the Sales group. Fine-grained password policies have
been configured as follows:
-
A fine-grained password policy having a precedence value
of 1 has been created and assigned to the Marketing
group.
-
A fine-grained password policy having a precedence value
of 2 has been created and assigned to the Sales group.
Because Karen belongs to both groups, both policies apply to
her, but the one with the lowest precedence value (the policy
assigned to the Marketing group) is the one that takes
effect.
Note that if two fine-grained password policies have the
same preference value and both policies apply to the same user,
the policy with the smallest globally unique identifier (GUID)
wins.
Best practices for implementing fine-grained password
policies
When planning to implement fine-grained password policies
within your Active Directory environment, you should follow these
best practices:
-
Assign policies to groups instead of individual users for
easier management.
-
Assign a unique preference value to each fine-grained
password policy you create within a domain.
-
Create a fallback policy for the domain so that users who
don’t belong to any groups that specifically have fine-grained
password policies assigned to them will still have password and
account lockout restrictions apply when they try to log on to
the network. This fallback policy can be either of the
following:
Note
REAL WORLD Implementing a
fallback policy for your domain
Consider a scenario where the corp.contoso.com has three
groups: Marketing, Sales, and Human Resources. Fine-grained
password policies have been configured as follows:
-
A fine-grained password policy having a precedence value
of 1 has been created and assigned to the Marketing
group.
-
A fine-grained password policy having a precedence value
of 2 has been created and assigned to the Sales group.
-
No fine-grained password policy has been assigned to the
Human Resources group.
To ensure that password and account lockout restrictions apply
when members of the Human Resources group try to log on to the
network, you can do either of the following:
-
Configure password and account lockout policy settings in
the Default Domain Policy GPO for the domain.
-
Create a fine-grained password policy that has a
precedence value of 100, and assign this policy to the Domain
Users group.
Note that the recommended approach is to use the second option
mentioned because Default Domain Policy is a legacy feature dating
back to the Windows NT era while fine-grained password policies are
the future.