What Is Container Networking Interface

Cni the container network interface is a standard api between container runtimes and container network implementations.

What is container networking interface.

This enables a container to attach to your host s network meaning the configuration inside the container matches the configuration outside the container. How is container networking helpful in web scale application deployments. The plugins support the addition and removal of container network interfaces to and from networks. Cni is defined by a spec read it now its not very long that has some interesting language in it.

There are two proposed standards for configuring network interfaces for linux containers. The container network model cnm and the container network interface cni. Unlike cnm cni doesn t require a distributed key value store like etcd or consul. This container only has a local loopback interface i e no external network interface.

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. Container networking interface aka cni. While there are various plugins created to integrate with each the latter has been somewhat ubiquitously adopted across the container orchestration landscape. A container runtime eg.

Containers in enterprise environments are often used as part of a microservices architecture. Cni assumes that the network configuration is in json format that can be stored in a file. Essentially the networking stack within a container it is an isolated environment to contain a container s network configuration. 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.

This offers a container specific network stack that lacks a network interface. This model is common for large web applications where many different applications handle individual tasks and communicate with one another via traditional ip networking. Endpoints join exactly one network and multiple endpoints can exist within a single. 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.

Defined by a json schema its templated code makes it straight forward to create a cni plugin for an existing container networking project or a good framework for creating a new container networking project from scratch. Cni stands for container networking interface and it s goal is to create a generic plugin based networking solution for containers.