Active Directory determines who can access which computer, folder and system. That is why it is a prime target for attackers: whoever takes control of the domain controls the entire company. These ten tasks form the foundation of a healthy, secure domain.
1. At Least Two Domain Controllers
If you have only one domain controller and it fails, user logins, file access and many services are disrupted. Run at least two domain controllers on two different hosts or physical servers, and check the health of replication between them regularly.
2. Back Up Active Directory
Take System State backups or full machine backups of your domain controllers and test restoring them. Restoring a domain is a scenario that is best rehearsed before a crisis.
3. Few, Separate Admin Accounts
- Keep membership in the Domain Admins and Enterprise Admins groups to a minimum.
- Administrators should use a regular account for everyday work and have a separate admin account.
- Do not log in to user computers with a Domain Admin account; its credentials stay in that computer’s memory and can be stolen.
4. Unique Local Admin Passwords with Windows LAPS
If the local Administrator password is the same on every computer, compromising one computer means access to all of them. Windows LAPS, built into recent versions of Windows and Windows Server, creates a unique, regularly rotated password for each computer and stores it securely in the domain.
5. Password Policy and Account Lockout
Set your password policy with a focus on adequate length, and enable temporary account lockout after several failed attempts to prevent password guessing. For sensitive accounts, you can apply a stricter policy with Fine-Grained Password Policy.
6. Disable Unused Accounts
Accounts of former employees and computers that have not connected to the domain for months are open doors that nobody is watching. Have a clear process for disabling accounts when employees leave, and review inactive accounts every few months.
7. An Organized OU and Group Policy Structure
Place users and computers in logical OUs (for example, by department or branch) so that Group Policies apply precisely and predictably. Remove unused or duplicate GPOs and write a description for each GPO.
8. Folder Permissions Based on Groups
Grant access to shared folders to groups, not to individual users. When an employee moves between departments, only their group membership changes, and their access updates automatically.
9. Healthy DNS
Many strange domain problems are actually DNS problems. Computers and servers should use only the domain controllers’ DNS (not internet DNS), stale records should be cleaned up with Scavenging, and internet Forwarders should be configured correctly.
10. Updates and Event Monitoring
Keep your domain controllers up to date; domain vulnerabilities are among the most dangerous. Monitor important events such as repeated failed logins, changes to admin group membership and the creation of new accounts, so that suspicious changes are spotted.
If your Windows Server version is out of Microsoft’s support period, it no longer receives security updates. Plan a migration to a supported version.
Conclusion
A healthy domain works quietly, while a disorganized one is a source of daily problems and major security risks. ITPlus724 engineers can assess the health of your Active Directory, report the issues they find, and make your company’s domain organized and secure.