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Kubernetes: 17. Application Logs

Docker Logs

  • docker run will shows the logs on the terminal
  • docker run when executed in detached mode "-d" will not show the logs on the terminal
  • To view the logs of container running in the detached mode we use docker logs command. Add "-f" flag to follow the live logs
Kubernetes Logs
  • Kubernetes pod logs can be viewed using kubectl logs command
  • If there are multiple containers running in the pod, provide the container name as input to the command
  • Use "-f" flag to "follow" the logs similar to docker
  • When using "-f" flag with kubectl create, it indicates create from the file specified in the command

docker run nginx 
-> Run a container on the terminal, logs will be be displayed

docker run -d nginx 
-> Run the container in the detached mode, logs will no more be displayed

docker logs -f nginx
-> display the logs of the container, -f (follows) will shows the live logs

kubectl logs -f <pod-name>
-> Shows the logs of the <pod-name> in the default namespace

kubectl logs -f <pod-name> -c <container-name>
-> Shows the logs of the <container-name> running in the <pod-name> in the default namespace



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