A domain controller is a server that manag

A domain controller is a server that manages authentication and authorization in a Windows domain.

What is a Domain Controller?

A domain controller is a server that runs Active Directory Domain Services and manages authentication, authorization and other directory services.

Functionalities

Authentication

  • Identity verification: Verify user identity
  • Credentials: Validate credentials
  • Sessions: Manage user sessions
  • Tokens: Issue authentication tokens

Authorization

  • Permissions: Manage permissions
  • Groups: Manage user groups
  • Policies: Apply group policies
  • Resources: Control resource access

Directory Services

  • LDAP: LDAP services
  • DNS: DNS services
  • Kerberos: Kerberos authentication
  • Replication: Data replication

Controller Types

Primary

  • PDC: Primary Domain Controller
  • Functions: Primary functions
  • Replication: Replication source
  • Changes: Accept changes

Secondary

  • BDC: Backup Domain Controller
  • Functions: Backup functions
  • Replication: Receive replication
  • Changes: Limited changes

Read-Only

  • RODC: Read-Only Domain Controller
  • Functions: Read-only
  • Security: Higher security
  • Locations: Remote locations

Configuration

Installation

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# Install Active Directory Domain Services
Install-WindowsFeature -Name AD-Domain-Services -IncludeManagementTools

# Promote to domain controller
Install-ADDSDomainController -DomainName "contoso.com" -InstallDns

Basic Configuration

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# Create user
New-ADUser -Name "John Doe" -SamAccountName "jdoe" -UserPrincipalName "jdoe@contoso.com"

# Create group
New-ADGroup -Name "IT Admins" -GroupScope Global -GroupCategory Security

# Add user to group
Add-ADGroupMember -Identity "IT Admins" -Members "jdoe"

Group Policies

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# Create GPO
New-GPO -Name "Security Policy"

# Link GPO to OU
New-GPLink -Name "Security Policy" -Target "OU=Users,DC=contoso,DC=com"

# Configure policy
Set-GPRegistryValue -Name "Security Policy" -Key "HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\System" -ValueName "DisableAutomaticRestartSignOn" -Value 1 -Type DWord

Security

Authentication

  • Kerberos: Kerberos protocol
  • NTLM: NTLM protocol
  • LDAP: LDAP authentication
  • Certificates: Certificate authentication

Authorization

  • ACLs: Access control lists
  • Permissions: Object permissions
  • Groups: Security groups
  • Policies: Group policies

Monitoring

  • Events: Security events
  • Logs: Audit logs
  • Alerts: Security alerts
  • Analysis: Behavior analysis

Replication

Types

  • Intrasite: Replication within site
  • Intersite: Replication between sites
  • Urgent: Urgent replication
  • Scheduled: Scheduled replication

Configuration

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# Verify replication
repadmin /showrepl

# Force replication
repadmin /syncall

# Verify connectivity
repadmin /replsummary

Monitoring

Tools

  • Event Viewer: Event viewer
  • Performance Monitor: Performance monitor
  • Task Manager: Task manager
  • Resource Monitor: Resource monitor

Commands

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# Verify service status
Get-Service ADWS

# Verify replication
repadmin /showrepl

# Verify DNS
nslookup contoso.com

Best Practices

Security

  • Hardening: Apply hardening
  • Patches: Keep updated
  • Monitoring: Monitor continuously
  • Backup: Backup regularly

Performance

  • Resources: Assign appropriate resources
  • Monitoring: Monitor performance
  • Optimization: Optimize configuration
  • Scalability: Plan scalability

Maintenance

  • Backup: Backup configurations
  • Documentation: Maintain documentation
  • Testing: Test changes
  • Updates: Apply updates

References