Azure Networking (VNet, NSG, Load Balancer)

Networking is the backbone of any cloud architecture. Azure provides a rich set of networking services to connect, protect, and deliver your applications. This lesson covers the core networking concepts you need to know.

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Azure Virtual Network (VNet)

A Virtual Network (VNet) is a logically isolated network in Azure. It's the fundamental building block for your private network, similar to a traditional network in a data centre.

Key Concepts

Concept	Description
Address space	The IP range for your VNet (e.g., 10.0.0.0/16)
Subnets	Subdivisions of the address space (e.g., 10.0.1.0/24, 10.0.2.0/24)
Region	A VNet exists in a single region
Subscription	A VNet belongs to a single subscription

Creating a VNet

az network vnet create \
  --resource-group rg-demo \
  --name myVNet \
  --address-prefix 10.0.0.0/16 \
  --subnet-name frontend \
  --subnet-prefix 10.0.1.0/24

Subnets

Subnets segment your VNet for organisation and security:

VNet: 10.0.0.0/16
  |
  |-- Subnet: frontend   (10.0.1.0/24) — web servers
  |-- Subnet: backend    (10.0.2.0/24) — application servers
  |-- Subnet: database   (10.0.3.0/24) — databases