Kubernetes vs Docker: Understanding Containers

Container technologies are sweeping the industry, and one of the most common online searches on the topic is ‘Kubernetes vs Docker’. It is questionable whether or not this comparison is accurate as it is not really comparing apples to apples. The two technologies are in fact fundamentally different and do not compete – it is not an either/or situation. As well as excelling in their respective fields, they are complementary and when combined can be extremely powerful.

In this post, we’ll explore the foundations of Kubernetes and Docker, as well as look at how each of them can be used individually and in conjunction. To begin, we must consider the technology that ties them together: containers.

What are containers?

Containers are executable programs that package application code with its dependencies, letting them run across different IT infrastructures. Containers are independent, abstracted from host operating systems (OS) – usually Linux – making them portable across IT environments. Often compared with virtual machines (VMs), they provide similar isolation and allocation capabilities. It is easier to travel with containers rather than virtual machines, as they only virtualize the OS as opposed to the hardware layer. The Linux kernel introduced containers in 2006 with the introduction of cgroups by Google.

What is Kubernetes?

Kubernetes is an open-source container orchestration platform that automates the deployment, management, and scaling of containerized applications. It is an incredibly flexible container tool for building complex applications. Containerized applications run on hundreds to thousands of individual servers. You can also manage your applications more efficiently. Containers are grouped into clusters using a concept called “clustering.” A Kubernetes cluster includes a container designated as a “master node” that schedules workloads for the other containers in the cluster.

Here are the essential features of Kubernetes:

  •     Scheduling can be automated
  •     The ability to heal itself
  •     Rollouts & rollbacks automated
  •     Load balancing and horizontal scaling
  •     Utilizes resources at a higher density
  •     Features enterprise-ready functionality
  •    Defines configuration declaratively

What is Docker?

Docker is an open-source platform for containerization.  Application packaging and the cloud have both benefited greatly from it. This system enables you to deploy applications in lightweight, portable containers automatically. This is a form of virtualization software. It is also capable of accommodating multiple operating systems simultaneously. In Docker, virtualization occurs at the system level using something called Docker containers.

Here are the essential features of Docker:

  •     You can manage your applications in isolated environments
  •     Easy to model
  •     Controlled versioning
  •     Position/Affiliation
  •     Flexibility in application development
  •     Productivity for developers
  •     Efficiencies of Operation

Difference between Kubernetes and Docker 

ParameterKubernetesDocker Swarm
Assembled byGoogleDocker Inc
Publication year20142013
ScalingAuto-scalingNo Autoscaling
ClusteringIt is easy to set up the cluster. A couple of commands are necessary. Not as strong as it could be.It is difficult and complicated to set up the cluster. It has stronger clustering.
Volume of dataStorage volumes can be shared between containers.Multi-container pods can share storage volumes.
Balancing the loadConfigure your load balancing settings manuallyLoad balancing is automatic
ScalabilityScaling up is slower than docker. Load balancing requires manual configuration but guarantees stronger cluster states.Faster scaling than Kubernetes. However, it does not have a robust cluster.
UpdatesUpgrading a cluster can be done on-site.Agent updates can be carried out in place.
For optimum performanceDesigned to optimize multiple smaller SDLC clustersDesigned for a single large cluster
Tolerance Low fault toleranceHigh fault tolerance
Provision of nodesProvides support for up to 5000 nodesProvides support for 2000+ nodes
Limit on containersContainers limited to 300000Containers limited to 95000
Cloud computing serviceGoogle, Azure, and AWS.Azure only.
SlaveNodesWorker
CompatibleCustomizable and more comprehensiveLess customizable and extensive
CommunitySupports open-source communities and big companies like Google, Amazon, Microsoft, and IBMRegularly updated software by an active user base.
Large clustersScales containers even in large clusters without taking into account speed.The speed of the strong cluster states is considered.
Companies using9GAG, Buffer, Evernote, Intuit, etc.Spotify, Pinterest, eBay, Twitter, etc.
Github Stars54.1 k53.8 k
Github forks18.7 k15.5 k

The final word

The containers are incredible. We can think about systems and services in a completely new and digital way with them. There will be no stopping Docker and Kubernetes – they will continue to evolve to become better systems in the future. Ensure that you implement containers that are needed by your infrastructure.

Designing apps for container-centric platforms will not only make them more scalable but will also allow them to be more future-proof. Even if you stick with the old virtual machines for a few years, you will eventually be forced to migrate everything into containers or abandon your projects entirely.