What is Pod in kubernetes. Explain 15 points with image as an example

Kubernetes Networking Guide for Beginners - Kubernetes Book
  • It is an atomic scheduling unit in a Kubernetes cluster.
  • It is a logical unit.
  • Every container running in the cluster nodes will be wrapped up by the POD.
  • In one POD there can be multiple container running. It is called tight coupling.
  • Prefered way is run one container in one POD. It is called loose coupling.
  • Each POD will have its own IP address.
  • There will be POD nw connecting all the PODS in a cluster irrespective of the nodes.
  • Can communicate with each container by <POD IP>:<Container port>
  • All the contaniers in a POD can share the POD environment like networking.
  • PODs can specify the shared storage volumes and every container in the POD can access it.
  • Inside the POD the containers can communicate using localhost.
  • Containers with in the POD can also communicate using any IPC mechanism.
  • Containers with in different PODs can’t communicate using any IPC mechanism, without some special configuration.
  • POD has only two states: Pending and Running.
  • PODs can’t be re-deployed. So all the data associated with PODS will be lost once, it is down.