VNets without public subnet

Overview

The VNets without public subnet insight identifies Azure Virtual Networks (VNets) that lack a public subnet. This information is critical for IT Operations (IT Ops) and Security Operations (Sec Ops) engineers to ensure proper network configuration and accessibility in their Azure environment.

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Value to IT and Security Engineers

For IT Engineers:

• Connectivity Assessment: Highlights VNets that may not support resources requiring internet or external connectivity, aiding in troubleshooting and design optimization.

• Operational Efficiency: Enables better network planning by identifying gaps in connectivity, ensuring that the required subnets are properly implemented for workloads needing public access.

• Scalability Support: Helps ensure VNets are configured for scaling requirements, such as enabling internet-facing applications or services.

For Security Engineers:

• Controlled Access Enforcement: Identifies cases where VNets intentionally lack public subnets, ensuring that restricted access aligns with security policies.

• Compliance Monitoring: Ensures configurations meet organizational and regulatory standards by identifying VNets that may lack appropriate subnet definitions.

• Risk Reduction: Confirms that sensitive workloads are isolated from the public internet when public subnets are not intentionally omitted.

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Key Use Cases

1. Network Configuration Audit: IT Ops can use this insight to verify that all VNets requiring public connectivity are correctly configured with public subnets.

2. Security Policy Verification: Sec Ops can confirm that VNets without public subnets are appropriately secured, ensuring that they align with the intended use case (e.g., private workloads).

3. Troubleshooting Connectivity Issues: IT Ops can quickly identify missing public subnets as a root cause for workloads experiencing connectivity issues.

4. Compliance Assurance: Sec Ops can validate that VNets adhere to compliance standards, ensuring that public subnet requirements are properly documented and managed.

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Actionable Insights

• Review Network Design: Assess whether VNets without public subnets align with the intended architecture and business requirements.

• Validate Isolation Needs: Ensure that VNets without public subnets are correctly designed for workloads that do not require internet access.

• Plan for Connectivity: For VNets requiring public connectivity, create and configure public subnets with appropriate security measures (e.g., network security groups).

• Audit Regularly: Schedule periodic reviews to ensure the network's configuration matches operational and security policies.

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Additional Recommendations

• Monitor Subnet Changes: Use Azure Monitor or Azure Policy to track and alert on changes to VNet and subnet configurations.

• Apply Security Controls: For VNets with public subnets, ensure proper security rules are applied to control access.

• Document Use Cases: Maintain clear documentation on the intended purpose of each VNet and its subnet configuration for compliance and operational clarity.

• Integrate DDoS Protection: For public-facing workloads, ensure that Azure DDoS Protection is enabled to safeguard against external threats.

The VNets without public subnet insight provides a critical perspective for IT Ops and Sec Ops to maintain a balanced, secure, and compliant Azure networking environment.