Active directory domain services is currently not available

Troubleshooting Active Directory Domain Services Unavailability Issues

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Active Directory (AD) is the core component of an organization's Microsoft Windows domain infrastructure, responsible for managing and providing access to resources across a network. When AD services become unavailable or non-functional, it can significantly impact user productivity and overall system performance.

In this article, we'll delve into troubleshooting strategies specific to resolving issues related to Active Directory Domain Services (AD DS) unavailability, focusing on common error messages and Event IDs that may indicate such problems.

Common Causes of AD DS Unavailability

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Before diving into the nitty-gritty of troubleshooting, it's essential to understand some of the most common causes behind AD DS becoming unavailable:

1. Incorrect or missing DNS entries: Ensure that both forward (FQDN) and reverse (PTR) records are correctly configured for all domain controllers in your Active Directory environment.

2. Network connectivity issues: Check whether there are any problems with network cables, switches, routers, or other networking components between domain controllers.

3. Active directory service not running on a server: Ensure that the AD DS role is installed and started on all intended servers within your Active Directory infrastructure.

4. Permissions-related problems: Verify proper permissions settings for user accounts and groups across relevant Active Directory objects to prevent access issues.

5. AD database corruption or failures: Corruption of either local or SYSVOL replicas can lead to replication conflicts, resulting in AD DS unavailability.

Event ID 132: 'Active Directory Domain Services is currently not available'

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This Event ID typically indicates that the Active Directory Domain Service (NETLOGON) service has stopped working on one or more domain controllers within your Active Directory forest. Here are some steps you can take to troubleshoot and resolve this issue:

1. Check event logs: Review system, security, and application event logs for any additional error messages or warning events that may provide further insight into the cause of AD DS unavailability.

2. Restart NETLOGON service: Attempt to manually start the NETLOGON service on affected domain controllers using either Services.msc (services console) or PowerShell with the following command: `net stop netlogon && net start netlogon`

3. Perform a forced restart: If manual restarting of services doesn't resolve the issue, consider performing an orderly shutdown followed by a cold reboot of all domain controller servers within your Active Directory environment.

4. Check AD replication health: Use tools like Repadmin.exe or nltest to verify that Active Directory replication is functioning correctly between sites and domains across your forest.

Event ID 100: 'Active Directory Domain Services Availability'

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This Event ID typically indicates an availability issue with the Active Directory service itself, rather than a specific domain controller within your AD infrastructure. Here are some steps you can take to troubleshoot and resolve this issue:

1. Check for DNS resolution problems: Ensure that both forward (FQDN) and reverse (PTR) records exist correctly for all domain controllers in your environment.

2. Verify proper installation of Active Directory Domain Services role: Check whether the AD DS role is properly installed on all intended servers within your Active Directory infrastructure using either Server Manager or PowerShell with the following command: `Get-WindowsFeature -Name 'ADDS-Active\Directory-Domain-Services' | Select-Object Name`

3. Check for active directory database corruption: Run a full consistency check (ntdsutil.exe) on all domain controllers within your Active Directory environment to identify and repair any potential data inconsistencies.

Troubleshooting ------------------------

In conclusion, AD DS unavailability issues can have far-reaching implications for organization-wide IT infrastructure stability and user experience. By understanding the common causes behind such problems - including DNS resolution errors, network connectivity issues, permissions-related problems, active directory service failures, and database corruption or replication conflicts - system administrators are better equipped to rapidly identify and resolve these critical availability concerns.

Remember that proactive monitoring of Active Directory services using built-in tools like Event Viewer, Performance Monitor (perfmon.exe), as well as third-party solutions from reputable vendors can help proactively detect potential issues before they escalate into full-blown AD DS unavailability incidents.

Active directory domain services is currently not available