Mastering Kubernetes - Second Edition

First look at the loopback plugin

The loopback plugin simply adds the loopback interface. It is so simple that it doesn't require any network configuration information. Most CNI plugins are implemented in Golang, and the loopback CNI plugin is no exception. The full source code is available at:

https://github.com/containernetworking/plugins/blob/master/plugins/main/loopback

Let's look at the imports first. There are multiple packages from the container networking project on GitHub that provide many of the building blocks necessary to implement CNI plugins and the netlink package for adding and removing interfaces, as well as setting IP addresses and routes. We will look at the skel package soon:

package mainimport ( "github.com/containernetworking/cni/pkg/ns" ...