Fail to make HTTPS requests in pod network (192.168.0.0/16)
I have created a new set k8s cluster, 10.100.1.1 (master), 10.100.1.2...10.100.1.5, pod internal network is 192.168.0.0/16
e.g. metrics-server is assigned to node3 (10.100.1.3), with pod ip address 192.168.12.123.
when I ssh to node3 and do a curl (curl -k https://192.168.12.123), it can return result
but if I ssh to nodes other than node3, and do a curl (curl -k https://192.168.12.123), it will return curl: (28) Operation timed out after 0 milliseconds with 0 out of 0 bytes received
Basically all cross-nodes pod HTTPS requests (192.168.x.x) fails
finally figured out the problem.
from calico config, the MTU is 1500 from ifconfig, the MTU of the interface is 1450
the solution is to kubectl edit configmap calico-config, change MTU value from 1500 to 1430, and restart.
this solves the issues
I think there is an issue with firewall between nodes in your cluster. Make sure that you open required ports between master and worker nodes in your Kubernetes cluster.
I hope it will be helpful