Why Kubernetes ?

Why Kubernetes ?

Kubernetes lets you deploy containers on a cluster(set of nodes(instances)). It is able to load balance traffic to containers and distribute the network traffic so that the deployment is stable.

• How Does Kubernetes do it ?
  For a stable deployment, kubernetes first creates a service with a fixed IP Address for your pods.

  ^{A service is the fundamental way Kubernetes represents load balancer(Network LB with public IP). It groups set of pods together and provides a stable endpoint for them.}

  By default pods in your deployment are only accessible in your cluster so to allow access over the internet, connect a load balancer and then kubernetes will create the service:

  $ kubectl expose deployments nginx --port=port --type=loadbalancer

  • To get service: $ kubectl get services
    • Any client that hits the service  ExternalIP  will be routed to the pods behind the service.



• Why do you need a service for a stable IP (Internet Protocol)?
  Since deployment create and destroy pods, the internal pods may not be stable, so a service to a stable IP is a better way to manage connections.

• Extra Notes:

  • Use declarative commands like config files to scale your deployments so you can update anytime and apply the new changes.
  • To avoid downtime while your app redeploys, use an update strategy (eg. RollingUpdate).
  • To view replicas: $ kubectl get replicasets
  • To see active pods: $ kubectl get pods
  • To check deployments: $ kubectl get deployments

reference url: None
published at: July 10, 2022, 9 a.m.

Post Category: Cloud , Development