Standard Load Balancer inbound NAT rule now supports specifying a range of ports for the backend instances. Previously, to enable port forwarding, an inbound NAT rule needed to be created for every instance in Load Balancer’s backend pool. This became complex to manage at scale and resulted in management overhead. Today, we are announcing the addition of port management for backend pool to inbound NAT rules. This allows you to specify a range of frontend ports pre-allocated for a specific backend pool to enable port forwarding.
Upon scaling, Standard Load Balancer will automatically create port mapping from an available frontend port of the specified range to the specified backend port of the new instance. This capability applies to all types of backend pools composed of Virtual Machines, Virtual Machines Scale Sets, or IP addresses across all Azure regions.
Learn more about inbound NAT rules.