Network Security Groups (NSGs)

Network Security Groups (NSGs) are stateful firewall rules that you can apply to Azure resources. They control inbound and outbound network traffic.

Key Features

• Stateful Firewall: NSGs track connections, allowing traffic that has been initiated from within the Azure resource.
• Rule-Based: Rules are based on IP addresses, ports, and protocols.
• Application-Based: Define NSGs based on the applications running on your virtual machines.
• Azure Resource Manager: Manage NSGs through the Azure portal, Azure PowerShell, or Azure CLI.

NSG Rules

NSG rules are configured using a source, destination, port, and protocol. You can also define actions, which can be 'Allow' or 'Deny'.

Best Practices

• Start with a Deny-All rule to secure your network.
• Use the principle of least privilege, only allowing the necessary traffic.
• Monitor NSG traffic using Azure Monitor.