AD-SUB-09: Distinct first two octets (/16 networks) count should be retrievable
| ID | AD-SUB-09 |
| Severity | Info |
| Suite | Active Directory (on-premises) |
| Product | Active Directory |
| Feature | Sites and subnets |
| Security area | Infrastructure hardening |
| Resource type | AdSite |
| Reads from | On-premises Active Directory |
What this checks and how to fix it
Section titled “What this checks and how to fix it”Understanding /16 network distribution helps:
- Network planning: Identify how many major network blocks are in use
- Segmentation analysis: Understand logical network boundaries
- Capacity assessment: Determine available /16 networks
- Documentation: Support network architecture documentation
Each /16 represents a major network segment (65,534 hosts).
Control Type
Section titled “Control Type”Operational
Security Recommendation
Section titled “Security Recommendation”- Document the purpose of each /16 network block
- Plan /16 allocation to support organizational structure
- Reserve /16 blocks for future expansion
- Review /16 utilization during network planning
How the Test Works
Section titled “How the Test Works”This test extracts the first two octets from all IPv4 subnets and counts the distinct /16 networks.
Related Tests
Section titled “Related Tests”Test-MtAdSubnetFirstOctetCount- Analyzes first octetsTest-MtAdSubnetFirstThreeOctetsCount- Analyzes /24 networksTest-MtAdSubnetTotalCount- Counts total subnets
Mito check. Author: soulemike. Open-source licences.
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