Is it possible to use kubernetes with net.ipv4.ip_forward=0

General Discussions
1

Cluster information:

Kubernetes version: 1.17.4
Cloud being used: bare-metal
Installation method: KubeAdm, \w Docker 19.03, Calico-CNI, Istio 1.5.4
Host OS: RHEL 7.9
CNI and version: calico
CRI and version: ?

Just have a simple question.

Is it possible to use kubernetes by using setting net.ipv4.ip_forward=0? Our security team considers enabling IPV4 forwarding a security vulnerability.

Would be glad if answered.

2

That’s an unusual assertion.

There may be some implementation of k8s networking that doesn’t need it, but I have not heard of one.

Fundamentally, every pod gets an IP, which makes every node a sort of router.