Enable Istio CNI plugin

This guide describes how to enable Istio CNI plugin on Charmed Kubeflow (CKF).

By default, Istio injects an init container in all Pods inside the service mesh, which configures each Pod's network traffic redirection to and from the Istio sidecar proxy. This operation requires elevated permissions: Kubernetes (K8s) RBAC permissions to deploy containers with the NET_ADMIN and NET_RAW capabilities, which can conflict with some organisations’ security policies.

The Istio CNI plugin is a replacement of that init container that resolves the security concerns by avoiding the need for elevated permissions while providing the same functionality.

Requirements

• A running Istio control plane deployed by istio-operators > 1.17/*.

Enable the plugin

You can enable the Istio CNI plugin by setting the following configuration values for the istio-pilot charm:

• cni-bin-dir: the path where the CNI binaries, which implement the CNI specification, are located in the host system where the Kubernetes control plane is deployed
• cni-conf-dir: the path where the CNI’s conflist files (in JSON format) are located in the host system where the Kubernetes control plane is deployed

Set both of these to enable the plugin:

• juju config istio-pilot cni-bin-dir=<path to cni bin dir in host>
• juju config istio-pilot cni-conf-dir=<path to cni conf dir in host>

These values vary on each K8s installation and depends on the CNI’s configuration. The defaults for some installations are /opt/cni/bin and /etc/cni/net.d respectively.

For example, in microk8s, these values are /var/snap/microk8s/current/opt/cni/bin and /var/snap/microk8s/current/args/cni-network. Refer to MicroK8s CNI configuration for more details.

See Network Plugins and CNI for further information.

Last updated 10 days ago.