After running kubectl run database --image mongo you see the status is "CrashLoopBackOff". What could possibly went wrong and what do you do to confirm?

"CrashLoopBackOff" means the Pod is starting, crashing, starting...and so it repeats itself.

There are many different reasons to get this error - lack of permissions, init-container misconfiguration, persistent volume connection issue, etc.

One of the ways to check why it happened it to run kubectl describe po and having a look at the exit code

 Last State:     Terminated
   Reason:       Error
   Exit Code:    100

Another way to check what's going on, is to run kubectl logs . This will provide us with the logs from the containers running in that Pod.