Two questions were very important to me when my interest was on Kubernetes :
- What is Kubernetes ?
- What Kubernetes is not ?
By answering to these two questions, i was sure to start from the right point and also know the responsibility of Kubernetes .
So let’s make a pragmatic responses about that .
💡What is Kubernetes ?
Kubernetes is a platform that wrap a huge number of services and capabilities ; these latter is growing day after day . From a top level we can say , the core functionalities of Kubernetes is it’s ability to manage containers across linux based infrastructure . But Kubernetes brings also a lot of feature such as :
- Managing Secrets
- Checking applications Health
- Scaling application : Scale app and down
- Auto Scaling
- Instance replication
- Discovering resource
- Naming Resource
- Monitoring resource
- Managing and mounting Storage system
- Providing security component : Authorization , Authentication
In one sentence the responsibility of K8S is
Platform for managing containerized workloads and services, that facilitates both declarative configuration and automation.
⛔️ What Kubenetes is not ?
The Common mistake is to say Kubernetes is a Paas !
Kubernetes is not a platform as a service (Paas) , in my opinion Rancher is a Paas for Kubernetes , It provide a high level configuration for kubernetes and provide some default configuration for Kubernetes to .
In fact Kubernetes doesn’t dictate many aspects of our system and leaves them up to us to manage them .
In facts Kubernetes does :
- not require a specific application type or a dependency framework
- not require a specific programming language
- not provide any database
- not provide any message queues
- allow us to choose our logging system
- allow us to choose our monitoring & alerting system
- ..etc