Before discussing Kubernetes vs. docker swarm, let’s make an understanding of containers.
What is a Container?
To understand containers, we also need to understand the scenario before containers.
Before containers, when a developer wanted to test or install an application, they installed the application on the server, and that application may need some dependencies to run. So, they need to set up all those dependencies on that server, and if they want to do it on different machines, they have to do all those steps again from the beginning. In usual scenarios, they may end up in some kind of problem with their application, and their application will fail to run correctly. The problem of an application failing to run correctly arise due to differences in configuration underlying library requirements and other dependencies.
Containers solve this problem by providing a lightweight, immutable infrastructure for application packaging and deployment.
- A container is a standardized, portable packaging for applications.
- A container is a standard unit of software that packages up code, and all the application dependencies, so the application runs fast and reliably from one computing environment to another.
- Bundles an application’s code with the related configuration files, libraries, and dependencies required for the application to run.
Kubernetes Vs. Docker Swarm
What is Docker?
- To run a container, we also need some software to containerize the application.
- Docker is an open-source tool for building, deploying, and managing containerized applications.
- Docker is a software platform that allows us to build, test, and deploy applications quickly.
- Docker packages software into standardized units known as containers that contain everything the software needs to run, including libraries, system tools, code, and runtime.
- Kubernetes (K8s) is an open-source, extensible container orchestration platform for containerized services and workloads management.
- Originally developed by Google, eventually handed it over to Cloud Native Computing Foundation (CNCF) for maintenance and enhancement.
- The cluster of Kubernetes includes a set of worker nodes (worker machine) that host Pods and the control plane (container orchestration layer) that manages the Pods and worker nodes in the cluster.
What is Docker Swarm?
- Docker Swarm or Swarm is also an open-source container orchestration platform native to Docker.
- Docker Swarm manages containers and ensures the application runs seamlessly across multiple nodes.
- The swarm cluster consists of Docker Engine deployed as manager nodes (to orchestrate and manage the cluster) and worker nodes (to run swarm services).
Pros & Cons of Kubernetes
|Large and active open-source community backed by Google.||Complex installation and setup process|
|Large adopted in the market and tested by big companies like Google, IBM, etc.||Management of the Kubernetes master takes specialized knowledge.|
|Available on the public cloud or on-premises, it supports all operating systems.||Requires additional tools like Kubctl, CICD workflow, etc.|
|Sustain and handle large architectures and complex workloads.||Updates from the open-source community require careful patching to avoid workload disruption.|
|Built-in monitoring and supports autoscaling, and self-healing capacity, also provide GUI.|
Pros & Cons of Docker Swarm
|Built for use with the Docker Engine||Less functionality than Kubernetes.|
|Easy integration with docker tools like docker CLI and docker-compose.||Limited extensions and customization.|
|Simple installation and set-up process for the docker environment.||Don’t have a GUI interface.|
|Any service, tool, or software that works on a Docker will effortlessly work with Docker Swarm.||Don’t have monitoring solutions. Need to rely on third-party applications.|
|Docker Swarm works with the docker CLI; no need to install a new CLI.|
Let’s discuss some major differences between Kubernetes Vs. Docker Swarm:
|Complex installation and setup process||Easy setup and installation process.|
|Can handle large and complex environments.||Can handle simple environments.|
|It is more powerful and more complex, with a high learning curve.||Limited functionalities, lightweight, and easy to use.|
|Support autoscaling||Manual scaling|
|Built-in Monitoring||Need third-party tools for monitoring.|
|Manual setup of the load balancer||Auto load balancing|
|Need for a separate CLI tool||Integrates docker CLI|
|Rolling updates progressively update the Pods one after the other.||Rolling updates progressively update the containers one after the other.|
|Automatic Rollback in case of failure.||No automated Rollbacks.|
|Storage Volumes are shared only between containers within the same Pod.||Can share Storage Volumes with any other container in the node.|
|In-built logging and monitoring tools in place.||Should use Third-party logging and monitoring tools.|
Author: Huma Tariq
Copyright The Cloudflare.