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