What Is Container Networking Interface

There are two proposed standards for configuring network interfaces for linux containers.

What is container networking interface.

To put it succinctly it is an interface between a network namespace and network plugin. A network interface that typically comes in pairs one end of the pair sits in the network sandbox while the other sits in a designated network. Endpoints join exactly one network and multiple endpoints can exist within a single. Cni assumes that the network configuration is in json format that can be stored in a file.

Cni is defined by a spec read it now its not very long that has some interesting language in it. While there are various plugins created to integrate with each the latter has been somewhat ubiquitously adopted across the container orchestration landscape. How is container networking helpful in web scale application deployments. This model is common for large web applications where many different applications handle individual tasks and communicate with one another via traditional ip networking.

This offers a container specific network stack that lacks a network interface. Cni stands for container networking interface and it s goal is to create a generic plugin based networking solution for containers. These slides are from the cloud native computing foundation s webinar and explain what cni is how you use it and what lies ahead on the roadmap. A container runtime eg.

Container networking interface aka cni. Cni container network interface a cloud native computing foundation project consists of a specification and libraries for writing plugins to configure network interfaces in linux containers along with a number of supported plugins cni concerns itself only with network connectivity of containers and removing allocated resources when the. Cni the container network interface what is cni. Essentially the networking stack within a container it is an isolated environment to contain a container s network configuration.

Containers in enterprise environments are often used as part of a microservices architecture. Cni the container network interface is a standard api between container runtimes and container network implementations. This container only has a local loopback interface i e no external network interface. This enables a container to attach to your host s network meaning the configuration inside the container matches the configuration outside the container.

The plugins support the addition and removal of container network interfaces to and from networks. Container network interface cni cni exposes a simple set of interfaces for adding and removing a container from a network.