CNI overview

Managing a network where containers can interoperate efficiently is very important. Kubernetes has adopted the Container Network Interface(CNI) specification for managing network resources on a cluster. This relatively simple specification makes it easy for Kubernetes to interact with a wide range of CNI-based software solutions.

With Charmed Kubernetes, these networking 'plug-ins' are deployed as subordinate charms with each node running as a kubernetes-master or kubernetes-worker, and ensure the smooth running of the cluster. It is possible to choose one of several different CNI providers for Charmed Kubernetes, which are listed below:

Supported CNI options

The currently supported CNI solutions for Charmed Kubernetes are:

By default, Charmed Kubernetes will deploy the cluster using flannel. To chose a different CNI provider, see the individual links above.

Migrating to a different CNI solution

As networking is a fundamental part of the cluster, changing the network on a live cluster is not straightforward. Currently it is recommended to create a new cluster with Charmed Kubernetes using the desired option. When federation becomes part of a future release of Kubernetes, such a migration should be manageable with no downtime.