You can now provision a NAT gateway as part of cluster creation or create an AKS cluster with a NAT gateway on an existing VNET, instead of configuring a NAT gateway manually.
A NAT gateway is a Network Address Translation (NAT) service. You can use a NAT gateway so that instances in a private subnet can connect to external services, but external services cannot initiate a connection.
With NAT gateway support, ingress traffic can be handled via the Load Balancer, and egress traffic can be distributed across up to 16 IP addresses, providing the potential for 64,000 concurrent UDP and TCP flows per IP.
Learn more.