If you initialize Kubernetes cluster with kubeadm check with the network team if the ranges you provide to kubeadm with –pod-network-cidr and –service-cidr does not overlap with intranet network ranges. Otherwise, pods/services won’t operate well and you might see anomalies in your Kubernetes environment.
Common default values:
Issue we experienced:
We have around dozen of Windows and Linux nodes. From time to time windows pods could not operate well in the pod network. Sometimes HNS network (service-cidr) overlapped with physical host-gw and broke the routing table so the windows k8s node could not contact the internal network servers/services as well. This happened on both flannel and calico network providers.
Remember pod-network and service-cidr can’t overlap either. They must be separated.
Kubernetes Office Hours discussion (34:48 minute explained):
Explained also in the official documentation:
Troubleshooting Kubernetes Networking on Windows