A workload may require splitting a cluster’s nodes into separate pools for logical isolation. This isolation can be supported with separate subnets dedicated to each node pool in the cluster. This can address requirements such as having non-contiguous virtual network address space to split across node pools.
To create a node pool with a dedicated subnet, pass the subnet resource ID as an additional parameter when creating a node pool.
az aks nodepool add \ --resource-group myResourceGroup \ --cluster-name myAKSCluster \ --name mynodepool \ --node-count 3 \ --vnet-subnet-id <YOUR_SUBNET_RESOURCE_ID>