I’ve built a cluster (v1.15.4) on hyper-v with
- linux node (master) - linux node (worker) - windows node (worker) - networking - flannel (host-gw) - mac spoofing enabled for vms
deployed win-webserver.yaml to test if windows is working. https://kubernetes.io/docs/setup/production-environment/windows/user-guide-windows-containers/
kubectl get pods -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES win-webserver-7779dc4df7-58qs2 1/1 Running 0 18m 10.42.2.41 node01 <none> <none> win-webserver-7779dc4df7-mb4sf 1/1 Running 0 18m 10.42.2.43 node01 <none> <none> win-webserver-7779dc4df7-w5kjt 1/1 Running 0 18m 10.42.2.44 node01 <none> <none> win-webserver-7779dc4df7-wm245 1/1 Running 0 18m 10.42.2.45 node01 <none> <none> kubectl get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.43.0.1 <none> 443/TCP 122m win-webserver NodePort 10.43.91.255 <none> 80:30378/TCP 72m
Deployment ran fine however containers running on windows can’t resolve dns and access internet.
DNS request from windows pod
DNS request timed out. timeout was 2 seconds. Server: UnKnown Address: 10.43.0.10 DNS request timed out. timeout was 2 seconds. DNS request timed out.
Also can’t access pods from linux using service.
curl http://10.43.91.255 --connect-timeout 30 curl: (28) Connection timed out after 30000 milliseconds
kubectl logs -n kube-system pod/kube-flannel-8dqcc -c kube-flannel I1015 12:48:40.437400 1 main.go:527] Using interface with name eth0 and address 192.168.x.x I1015 12:48:40.437491 1 main.go:544] Defaulting external address to interface address (192.168.x.x) I1015 12:48:40.538336 1 kube.go:126] Waiting 10m0s for node controller to sync I1015 12:48:40.538380 1 kube.go:309] Starting kube subnet manager I1015 12:48:41.538500 1 kube.go:133] Node controller sync successful I1015 12:48:41.538539 1 main.go:244] Created subnet manager: Kubernetes Subnet Manager - node02 I1015 12:48:41.538551 1 main.go:247] Installing signal handlers I1015 12:48:41.538676 1 main.go:386] Found network config - Backend type: vxlan I1015 12:48:41.538751 1 vxlan.go:120] VXLAN config: VNI=4096 Port=4789 GBP=false DirectRouting=false W1015 12:48:41.539007 1 device.go:84] "flannel.4096" already exists with incompatable configuration: vtep (external) interface: 2 vs 3; recreating device I1015 12:48:41.632647 1 main.go:317] Wrote subnet file to /run/flannel/subnet.env I1015 12:48:41.632666 1 main.go:321] Running backend. I1015 12:48:41.632675 1 main.go:339] Waiting for all goroutines to exit I1015 12:48:41.632695 1 vxlan_network.go:60] watching for new subnet leases E1015 13:01:19.765370 1 vxlan_network.go:101] error decoding subnet lease JSON: invalid MAC address E1015 13:11:30.468144 1 vxlan_network.go:101] error decoding subnet lease JSON: invalid MAC address
Any suggestion appreciated.
I managed to get my cluster working. Reason for the communication failure was that I had two networks connected to each of kubernetes machines.
linux master - internet facing eth0 (192.168.6.2) eth1 (192.168.3.12) linux worker - internet facing eth0 (192.168.6.3) eth1 (192.168.3.13) windows node - internet facing Ethernet_LB (192.168.6.4) Ethernet_FW (192.168.3.14)
Virtual Switch on windows was created on Ethernet_FW which had no internet connection.
After running Wireshark and tdcdump I was able to find out that
- pods on master send traffic to windows pods via eth0
- pods on windows node send traffic to linux pods visa Ethernet_FW
- pods from windows send traffic to the internet via Ethernet_FW
That caused communication failure between pods.
I was able to configure windows node to create Virtual Switch on Ethernet_LB which had internet access and this interface (Ethernet_LB) was accepting packets from master and linux worker.
For cluster creation I used this resource https://kubernetes.io/docs/setup/production-environment/windows/user-guide-windows-nodes/
I had to put proper interface name into config file
"InterfaceName" : "Ethernet_LB"