Box 1: 10.244.0.0/16 -
The Pod CIDR.
Note: The --pod-cidr should be a large address space that isn't in use elsewhere in your network environment. This range includes any on-premises network ranges if you connect, or plan to connect, your Azure virtual networks using Express Route or a Site-to-Site VPN connection.
This address range must be large enough to accommodate the number of nodes that you expect to scale up to. You can't change this address range once the cluster is deployed if you need more addresses for additional nodes.
Box 2: 10.0.0.0/16 -
The --service-cidr is used to assign internal services in the AKS cluster an IP address.
Reference:
https://docs.microsoft.com/en-us/azure/aks/configure-kubenet
