Kubernetes Vs Docker, the most common phrase from technical people in today’s Cloud Computing world and they are in confusion what should they choose? Why leading public cloud providers like AWS, Google, Azure, etc. are running behind Kubernetes & Docker and implementing in their cloud and providing those services to its customers? What is Docker? What is Kubernetes? What is the difference between them?
Let’s look into Docker first and then Kubernetes and finally the differences. Before listing the differences, we have to understand the word containerization & Docker & Kubernetes.
What is Containerization?
Bundling an application’s configuration files, libraries & respective dependencies to run in an efficient and bug-free way across different computing environments.
Fig: What is Containerization?
Most popular containerization engines are Docker & Kubernetes.
What is Docker?
Docker is a standalone application which can be installed on any computer to run containerized applications.
Fig: Docker Architecture
What is Kubernetes?
A container-orchestration system for automating deployments, scaling & Management.
Fig: Kubernetes Architecture
- Docker & Kubernetes work separately and delivers efficient results in real-time environments but if docker and kubernetes work together, the outcome will more than individual.
- To be a robust environment, all the applications should be online I.e., even when one server goes down, other servers will deliver the same without any loss and user doesn’t feel the difference.
- Kubernetes is mainly used for scaling in-order to increase workload by creating more number of docker containers for single application.
Kubernetes VS Docker Swarm:
Remainder – Docker is a Containerization platform whereas Docker Swarm & Kubernetes are container orchestration platforms. Following factors, were taken into consideration for listing the differences:
- Installation & Cluster Configuration
- Load Balancing
- Rolling updates & Rollbacks
- Data Volumes
- Logging & Monitoring
Installation & Cluster Configuration:
Docker Swarm installation needs only 2 commands
- docker swarm init – -advertise-addr <ipaddress:portnumber>
- docker swarm join – -token <swarm cluster token> <ipaddress:portnumber>
Kubernetes has many steps in installation.
- Setting up environment variables.
- Installing kubeadm, kubelet, kubectl
- Starting kubernetes cluster from master
- Joining the worker nodes.
Kubernetes installation process is tough than docker swarn.
Docker swarm doesn’t provide any dashboard for accessing its cluster but with commands we can easily control docker swarm whereas Kubernetes has dashboard which run on localhost:8001 which is very easy to use.
Both Docker Swarm and Kubernetes has equal strength at scaling containers. Kubernetes basically deals with clusters and it can handle containers scaling (Horizontal/Vertical) efficiently whereas Docker Swarm works with 5x faster in scaling.
With K8s, Kubernetes behaves cleverly in analysing server workloads and does scale up/down accordingly whereas docker swarm supports only manual way of scaling.
In kubernetes, multiple containers are considered as 1 pod and these pods should communicate each other but all these pods runs on service based where there’s no ip address which makes the load balancing tough and is done manually whereas docker swarm has ipaddress for each container and they communicate each other and load balancing can be done easily and automatically.
Rolling updates & Rollbacks:
Both support rolling updates, but in rollback, whenever problem occurs while deploying, kubernetes does it automatically whereas docker swarm doesn’t.
Kubernetes shares the storage volumes between pods and easily mounted on local storage, any public clouds, NFS whereas Docker swarm also share storage volumes with any container.
Logging & Monitoring:
As we know Kubernetes has dashboard, along with that it also has logging & monitoring which is inbuilt, whereas Docker swarm uses 3rd party tools like ELK, Splunk, Graylog, etc.
These are the basic parameters which we consider for differentiating docker swarm and kubernetes. With hands-on experience many more parameters comes out and should take into consideration based on requirement. We (VirtueTechInc), support both and we suggest based on customer requirement but we recommend using Docker saves time in understanding the concept for developing/running good and efficient applications for small scale industries so that cost on infrastructure can cut down whereas if small scale industries are upgrading to cluster, then we recommend Kubernetes.