The OKD cluster uses a virtualized network for Pod and Service networks. The OVN-Kubernetes Container Network Interface (CNI) plug-in is a network provider for the default cluster network.

OVN-Kubernetes features

The OVN-Kubernetes default Container Network Interface (CNI) network provider implements the following features:

  • Uses OVN (Open Virtual Network) to manage network traffic flows. OVN is a community developed, vendor agnostic network virtualization solution.

  • Implements Kubernetes network policy support, including ingress and egress rules.

  • Uses the Geneve (Generic Network Virtualization Encapsulation) protocol rather than VXLAN to create an overlay network between nodes.

Supported default CNI network provider feature matrix

OKD offers two supported choices, OpenShift SDN and OVN-Kubernetes, for the default Container Network Interface (CNI) network provider. The following table summarizes the current feature support for both network providers:

Table 1. Default CNI network provider feature comparison
Feature OVN-Kubernetes OpenShift SDN

Egress IPs

Supported

Supported

Egress firewall [1]

Supported

Supported

Egress router

Not supported

Supported

Kubernetes network policy

Supported

Partially supported [2]

Multicast

Supported

Supported

  1. Egress firewall is also known as egress network policy in OpenShift SDN. This is not the same as network policy egress.

  2. Does not support egress rules and some ipBlock rules.