Kubernetes how to expose a port on host node to pods?

Solution 1:

As @David Tinker mentioned in the comments, problem is solved.

connections from inside k8s pods on the same host would get blocked by our firewall rules.

So, the solution is hidden in iptables:

iptables -A INPUT -p tcp --dport 8500 -j ACCEPT
iptables -A INPUT -i cni0 -j ACCEPT