K8S Services

Service is used to expose PODS

We have 3 types of services in K8S

  1. Cluster IP
  2. Node port
  3. Load Balancer

Cluster IP: 

  • If we want to expose PODs with in the Cluster, then Cluster IP is used
  • POD is short lived object
  • If POD is damanged/deleted/creashed then K8S will replace that with a new POD(self healing)
  • when pod is re-created IP will be changing(It is not recommented to access pods using POD IP)
  • Cluster IP service is used to link all PODS in Single IP
  • Cluser IP is a static IP to access PODS
Node port: 
  • If we want to expose PODs outside the Cluster, then Node port service is used
  • Using node port we can access our app with worker node public 
  • When we use worker node IP to access our POD then all requests will go to same worker node (Burden will be increased on the node)
  • To distribute load to miultiple worker nodes we will use Load Balancer service

Load Balance: 

  • It is used to expose our PODS outside cluster AWS Load balancer
  • When we access load balancer url, requests will be distributed to all pods running in all worker nodes.



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