NSG (Network Security Group)
An NSG filters network traffic to/from Azure resources using security rules.
Updated: 2026-03-05
Definition
NSGs control inbound and outbound traffic using rules based on source/destination, ports, and protocols.
They can be applied to subnets or network interfaces to segment and protect workloads.
Key points
- Rule-based filtering (ports/protocols)
- Can apply at subnet or NIC level
- Order/priority of rules matters
Common mistakes
- Creating overlapping rules with unclear priorities.
- Assuming NSG is the same as Azure Policy (different layers).
Related exams
Related terms
Want to practice this in exam-style questions?
Use the mini tests on each exam page, then continue in the app for offline packs and detailed explanations.
Go to exams