Kubernetes vs Docker

With Docker, you can develop, ship, and run applications in divided containers. Kubernetes helps you automate, scale and manage containerized applications.

Digital Quality
12 min
Digital Quality
Kubernetes vs Docker

Kubernetes vs Docker is a hot topic in the developer community. Each has several common features. However, they have differences that make one ideal over the other. The decision depends on your environment. You may decide you need both.

Docker and Kubernetes are technologies that enable developers to deploy and manage applications in virtual environments for better performance, scalability, and resilience than traditional methods.

Docker consolidates applications into small isolated environments that they can move around independently of the infrastructure.

Kubernetes automates managing those environments. When discussing Kubernetes vs Docker, the comparison isn’t so straightforward.

Here, we’ll discuss each one, the pros and cons of each, and give you some reasons why you might use both. Adservio helps companies evaluate each to determine the best implementation option.

How does Kubernetes work?

Kubernetes (K8s) is a cloud-native, open-source, container orchestration platform that manages the tasks required to run. Kubernetes handles tasks such as deployment, managing workloads, and scaling for containers.

What is Kubernetes used for?

One of the main benefits Kubernetes offers is that it provides resilience for containerized applications. With Kubernetes in charge, the platform automatically handles issues that may arise to keep the system running. A few of the other reasons developers use the platform are:

Service discovery

Kubernetes manages IP addresses and the DNS service to expose containers to incoming traffic. If the application’s workload increases, the Kubernetes platform serves as a gatekeeper and distributes that workload across containers.

Load balancing

In many systems, the workload varies. Traditionally, a workload spike could take an application offline. Kubernetes serves as a gatekeeper that distributes the workload across containers.

Managing storage

As applications grow and need more storage, Kubernetes handles provisioning additional storage. It automatically mounts storage from a cloud service provider or local storage system.

Automated rollout and rollback

Kubernetes enables developers to create configuration files to handle switching containers to desired states within the environment.

That way, Kubernetes can automatically roll out and roll back using configuration files.

Self-healing capabilities

With the platform, applications won’t suffer performance problems if a container fails. The platform can restart or replace a failed container. T

hat way, the container won’t receive additional traffic. Our clients rely on Adservio for our expertise in helping them implement Kubernetes for optimal performance.

Secret and configuration management

Kubernetes lets developers store information such as passwords, tokens, and SSH keys with encryption.

Kubernetes Architecture

Kubernetes packages containers into what are known as pods. These pods are what Kubernetes manages. Pods run on nodes.

A node is either a virtual server in a cloud environment or an on-premises server. Kubernetes groups nodes together into what is known as Kubernetes clusters.

This allows the tool to manage multiple nodes at once. Nodes have one of two assigned functions: a master node or a worker node.

Master Node
  • Kube-apiserver: Receives requests to manage Kubernetes components
  • Etcd: Backup storage for cluster configuration data
  • Kube-scheduler: Schedules and assigns pods to nodes
  • Kube-controller-manager: Runs controller processes each in a separate process.
Worker Node
  • Kubelet: Verifies that containers start and run appropriately
  • Container runtime: The runtime represents the container itself
  • Kube-proxy: Assigns IP addresses and performs session management

How does Docker work?

Docker is open-source software for running applications and microservices based on containers in a virtualized Linux environment.

Containers are small lightweight virtual machines that serve as execution environments. These environments "contain” applications along with the libraries, configuration files, and dependencies needed to run that application.

Containers share the same operating system, however, they run in isolation from each other. This makes container deployment simpler than with traditional deployment methods.

What is Docker used for?

Developers use the platform to deploy applications. Traditionally, teams deployed applications onto the same server. That meant applications could conflict with one another due to varying configuration requirements for each.

Another common issue was that what worked on the developer's machine didn’t work in production due to configuration and environment incompatibilities between the two.  

Developers can deploy containers independently of the infrastructure. They can move them from one server to another without worrying if it will work on another server.

An additional benefit of Docker containers is that they make more efficient use of the host operating system’s resources. This is because each container runs in a separate process in the user space on the host.

Docker Architecture

From an architecture perspective, the tool runs in what is called the Docker Engine. The engine contains three components that work together to make the platform work. The Server, The REST API, and a Command Line Interface (CLI).

docker architecture, the server, docker Daemon, the rest API and Docker CLI, command line interface (client)

The Server is a daemon process (Docker) on the operating system. The REST API sends instructions to the daemon. Clients use the CLI to manually send commands to the daemon process.

At the core of Docker is what is referred to as a container image. An image is a template with instructions that the engine uses to build an application container.

The platform coordinates work using three components: the Client, the Host, and the Registry.

Client: Developers interact with the tool by sending commands through the client using the Docker CLI. The client sends commands to docker which executes the instructions.

Host: The Docker daemon runs on the Host. The Docker daemon creates containers based on Docker images

Registry: The registry, also called Docker hub, hosts images. Developers access the registry to locate and reuse images for their applications.

Registries are either public or private. Any developer can use a public registry to find images. Private registries hold applications where only certain developers have access. Companies typically create private registries for internal developers to use.

The Rise Of Containerization And Docker

As complexity grew, developers needed a more efficient way to manage their applications. Containerized applications make for easier deployments and they scale easily.

Containerization also grew popular as many companies began looking for ways to modernize monolithic applications.

Containers enable companies to break these applications into small chunks called microservices.

Kubernetes vs Docker - which is better?

The Kubernetes vs Docker debate is a popular one. This is simply because many people do not know the full capabilities of each to fully compare the two.

As we’ll see, Kubernetes vs Docker is not a fair comparison. Instead of trying to decide between Kubernetes vs Docker, you need to look at both because you may find a reason to use both.

Docker is mainly a containerization platform, while Kubernetes is mainly a container orchestration platform. We say mainly because there are similarities between both. However, they are fundamentally different.

Kubernetes vs Docker differences on;

Runtimes: Both tools have container runtimes. Docker has a container as its runtime. Kubernetes has container + CRI as its runtime.

Kubernetes vs Docker: Orchestration: Both perform container orchestration. When it comes to container orchestration Docker has a native container orchestration platform called Docker Swarm.

However, Kubernetes has more robust features for its orchestration capabilities. That said, many people use both together which we’ll discuss below. Here are a few other comparisons of Kubernetes vs Docker:

Kubernetes vs Docker: Automated Deployments: Both Docker and Kubernetes support repeatable and consistent deployments.

Kubernetes vs Docker: Scalability and Container Management: Kubernetes makes better usage of resources for auto-scaling. It also handles more complex deployments. Kubernetes can also self-heal which makes it ideal for DevOps continuous integration environments.  

Kubernetes vs Docker: Learning Curve: Docker is easier to learn than Kubernetes. The many advanced features make managing Kubernetes a bit more challenging.

Kubernetes and Docker- Better Together

Both Docker and Kubernetes are great container technology tools. Each excels in distinct areas and has benefits over the other.

Docker is a robust virtualization platform that lets developers package and ship applications efficiently. Docker is the key to ensuring application compatibility across platforms.

Kubernetes is an orchestration tool and lifecycle management that ensures system stability and reliability through load balancing and workload scheduling. Together, they form a powerful solution that streamlines the DevOps pipeline.

How Adservio Can Help

Today’s modern businesses are embracing digital deployment efforts that require robust, resilient, scalable, and high-availability IT environments for superior user experiences.

As your business grows, an application environment that continues to operate with the same superior performance day after day is what you need.

Any business looking to upscale their environment can reach out to us for assistance. We can help guide you through evaluating Kubernetes vs Docker.

Reach out and let us assist you with implementing a solution that brings you maximum value for your digital transformation projects.

Published on
March 14, 2022

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