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Distinct first octets count should be retrievable

AD-SUB-08InfoActive DirectorySites and subnets

Part of Active Directory · Active Directory · Sites and subnets · All checks

Run this check
Invoke-Maester -TestId AD-SUB-08

Analyzing subnet distribution by first octet provides:

  • Addressing scheme visibility: Understanding IP allocation patterns
  • Network segmentation insight: How the network is logically divided
  • Capacity planning: Identifying available address space
  • Documentation: Supporting network topology documentation

Common patterns include using 10.x for corporate, 172.x for datacenters, etc.

Operational

  • Document the IP addressing scheme and first octet allocation
  • Plan address space to avoid conflicts during acquisitions
  • Reserve address space for future growth
  • Review addressing scheme during network architecture changes

This test extracts the first octet from all IPv4 subnets and counts the distinct values.

  • Test-MtAdSubnetFirstTwoOctetsCount - Analyzes /16 networks
  • Test-MtAdSubnetFirstThreeOctetsCount - Analyzes /24 networks
  • Test-MtAdSubnetTotalCount - Counts total subnets
Every attribute of this check
FieldValue
Test IDAD-SUB-08
SeverityInfo
SuiteActive Directory
ProductActive Directory
FeatureSites and subnets
AreaInfrastructure hardening
Resource typeAdSite
MITRE ATT&CKNone
PowerShell testTest-MtAdSubnetFirstOctetCount
ServicesActiveDirectory
PermissionsActiveDirectory:Ldap:subnet:ReadProperty