Network Automation Cookbook

How it works...

Azure provides default NSGs that are attached to subnets. These provide basic security controls to the computer resources deployed in these subnets. The default policy includes these default rules for inbound traffic:

• Allow inbound traffic between virtual network CIDR ranges (inter-subnet communication).
• Allow inbound traffic from Azure load balancers.
• Deny any other traffic.

In the outbound direction, the default rules are as follows:

• Allow outbound traffic between the virtual network CIDR (inter-subnet communication).
• Allow outbound traffic to the internet.
• Deny any other traffic.

Azure NSGs provide a mechanism to augment the default NSG applied by Azure by defining a custom NSG that is appended to the default one. The ...