Although containers provide many advantages, they also offer a host of new complexities. Especially as the concept of micro-services has become more prominent.
The need to not only create containers but better manage them has become important. Next, we will discuss three of the currently popular container and container management technologies.
You can’t talk about containers without talking about Docker.
Many people assume that Docker was the first container technology but that’s not the case. The Linux academy has a great history of containers if you would like to learn more.
Now on to Docker.
Docker is an open-source project based on Linux containers. This container engine was developed on Dotcloud. Docker gives developers the ability to focus on writing code without having to worry about the system the application will be running on.
Docker has a client server-architecture. This means that the Docker server is responsible for all container-related actions. This server receives commands via Docker client using REST API’s or CLI.
There are further nuances worth looking into. We recommend reading Stackify’s Docker Image vs container as it covers some of these very well.
Docker Image vs Container: Everything You Need to Know
Docker is a powerful tool for creating and deploying applications. It simplifies rolling out applications across…
Initially developed by Google, Kubernetes is an open-source system used for managing containerized applications in different environments. The main aim of this project is to offer better ways of managing services or components of an application across varied infrastructures. The Kubernetes platform allows you to define how your application should run or interact with the environment. As a user, you can scale your services and perform updates conveniently.
Kubernetes system is built in the form of layers, with each layer abstracting complexity found in lower levels. To begin with, the base layer brings virtual and physical machines into a cluster via a shared network. Here, one of the servers functions as a master server and acts as a gateway to expose an API for the clients and users.
From here there are other machines that act as nodes that get instructions from the master on how to manage the different workloads. Each node needs to have some form of container software running on it to ensure it can properly follow the instructions provided by the master node. To get a really good understanding, Digital Ocean further elaborates on this topic.
Helm is an application package manager which can be used to run on top of Kubernetes. This program allows you to describe application structure via helm-charts, managed through simple commands. Helms is a drastic shift, redefining how server-side applications are managed, stored, and even defined. This manager simplifies the mass adoption of microservices so you can use several mini services instead of monolithic application. Moreover, you can compose new applications out of existing loosely coupled microservices.
This tool streamlines the management and installment of Kubernetes applications by rendering templates and communicating with the Kubernetes API. This manager can be easily stored on disk and fetched via chart repositories such as RedHat packages and Debian.
How does Helm work?
Helm groups logical components of an application into a chart so you can deploy and maintain them conveniently over an extended time period. Each time a chart is deployed to cluster, a server-side component of Helm creates its release. This release tracks application deployment over time. With Helm, you can deploy almost anything virtually — from Redis cache to complex web apps.