What is subnet delegation, and where and when should we use it? You might have gone through multiple internet pages but still confusing, below hopefully.
This comes when you are dealing with PaaS services, PaaS services have a public endpoint and you want to connect with your Interanet System.
For example, If you would like to connect Azure NetApp Files or Azure Databricks, You basically grant the DataBricks service or NetappFiles to control certain aspects of a subnet, within an existing VNet. This process is referred to as Subnet Delegation. It allows a PaaS service to make certain configuration changes, like adding Network Security Group rules (if a subnet is attached to an NSG) or configure custom routes.
You can only delegate a subnet to a single resource type. That’s why you often create dedicated subnets for Azure PaaS services.
Let me know what do you think :)