What you will learn from this article:
There are so many moving parts related to Active Directory (AD). So, it is important to know how to monitor, report, fix and diagnose issues related to the different supporting technologies. Identifying bottlenecks and resolving them before they cause much harm improves productivity, ensures efficient usage of resources, maintains consistency in data and service, and ultimately reduces the number of help desk tickets. In this article, we will take a look at the key aspects that run an AD environment, and the steps you can perform to ensure that everything is working as it should be.
Some of the key aspects that help support and maintain AD include the following:
- The domain name system (DNS)
- AD replication
- AD backups
- Dynamic host configuration protocol (DHCP)
The steps given below show how you can ensure that each of the mentioned aspects is functioning properly.
Domain Name System, or DNS for short, is a name resolution method that is used to resolve hostnames to IP addresses. It is used on TCP/IP networks and across the internet. Active Directory is built on DNS. AD DS has an in-built method for storing these DNS records and then replicating them. They are called DNS zones. You can learn more about DNS in Active Directory in this article. For the purpose of this AD maintenance checklist, we can start with these DNS zones. Here is a DNS maintenance checklist you can perform:
- Checking the DNS zones and removing obsolete ones. The cleanup and removal of stale zones and resource records is required to prevent its accumulation in zone data, and to improve responsiveness.
- Checking name servers and removing Windows Internet Name Service (WINS) dependencies. AD is DNS intensive, and so WINS dependencies can be removed.
- Checking DNS for dormant static records, and configuring DNS scavenging. DNS scavenging removes stale and orphaned DNS records from the database.
- Clearing the DNS cache. Clearing all entries from the DNS forwarding cache helps in updating new DNS information.
- Updating root hints. Root hints configure authoritative servers of non-root zones to discover other authoritative servers that exist in other sub-trees or higher levels.
- Allowing only secure dynamic updates for all DNS zones. This ensures that only authenticated users can submit DNS updates using a secure method that prevents IP addresses from being hijacked.
- Securing the DNS Server. This process secures access control of the DNS Server service.
AD Replication maintenance
AD replication is another integral role in the AD environment. In any organization, large or small, it is imperative that directory data is regularly updated and made available for access to all users. For example, when an employee’s telephone number is modified, it must be communicated throughout the organization ensuring information is up-to-date in every domain controller. This process of updating information throughout the AD environment is accomplished through a mechanism called replication. Simply put, AD replication is the process by which copies of directory data are created and maintained in several domain controllers, and any changes made to the copies are passed to all other copies to ensure up-to-date information. Here is the AD replication maintenance checklist:
- Checking if replication is working properly and within the acceptable limits. Replication is critical to the availability and consistency of data across domain controllers (DCs). If replication fails between DCs, several aspects of AD would become unavailable.
- Verifying if all DCs are communicating with the central monitoring console, and examining all replication alerts on DCs. Examining and resolving alerts regularly can avoid service outages to some extent. A communication failure between the DC and the monitoring infrastructure creates problems in receiving these alerts.
- Verifying that all DCs are running with the same service pack and hot fix patches. If DCs run with different versions of software, it may cause problems.
- Reviewing trust relationships in the forest, and removing broken trusts. Communication and authentication between domains or forests requires trusts to be formed between the domains or forests. Any broken or stale trust relationship between domains should be removed.
AD Backup maintenance
Backups are always a good thing. Anything can go wrong at any time. In such cases, having a backup can ensure that important data and configurations are not lost, and months of time spent configuring settings or organizing data are not wasted. Here is an AD backup checklist that you can follow:
- Capturing system state information related to the AD database, logs, registry, boot files, SYSVOL and other system files. Regular backups help in restoring the most recent information in AD in case something goes wrong.
- Backing up GPOs. Regular GPO backups ensure that corrupted GPO objects are not a setback that may lead to consequences such as unnecessary privileges to user accounts and more.
Dynamic host configuration protocol, or DHCP for short, is an internet protocol that dynamically assigns IP addresses to devices. In AD, a server can be authorized for the role of DHCP. Here’s what you can check to keep DHCP working efficiently:
- Checking logs and monitoring real-time data. Checking logs identifies critical DHCP related events. It is recommended to implement a proactive monitoring solution for real-time data.
Other maintenance aspects
Apart from the four aspects mentioned above, there are several other areas to inspect that you can add to your AD maintenance checklist to ensure a properly functioning environment:
- Checking event logs. Event logs help in identifying if anyone has performed a sensitive administrative task. It is important to keep the log data secure and safe from tampering for performing accurate log forensic analysis.
- Managing privileged accounts. Managing users and groups that possess administrative privileges is necessary to prevent security breaches. Tracking changes made to privileged accounts helps detect any malicious activity.
- Checking for inactive user accounts. Having unused or inactive user accounts in AD is a security concern, as attacks on or using them may go unnoticed. It is better to remove such accounts unless absolutely necessary.