I am using the following command to check logs in Kubernetes.
kubectl logs pod_name -n namespace
It is printing all the logs from the beginning.
Thanks
Is there anyway to tail the logs or check logs between the given window?
To tail the logs, use the -foption
kubectl logs pod_name -n namespace -fIs it possible to role docker logs based on size or date?
You can query logs x-lines ago or since a time range. Take a look at the —tail and —since options
kubectl logs [-f] [-p] POD [-c CONTAINER]
Examples Return snapshot logs from pod nginx with only one container
kubectl logs nginx
Return snapshot of previous terminated ruby container logs from pod web-1
kubectl logs -p -c ruby web-1
Begin streaming the logs of the ruby container in pod web-1
kubectl logs -f -c ruby web-1
Display only the most recent 20 lines of output in pod nginx
kubectl logs --tail=20 nginx
Show all logs from pod nginx written in the last hour
kubectl logs --since=1h nginx
https://kubernetes-v1-4.github.io/docs/user-guide/kubectl/kubectl_logs/
kubectl logs pod_name --since=2m --timestamps
The "tail" functionality of "kubectl logs" can be used with this convenient GUI frontend: https://retrospective.centeractive.com/blog_retrospective_5_0_0.html
The frontend leverages several functions of "kubectl", for example:
Disclosure: I helped in making this frontend.
Yes, we can extract the log by using the since like below -
kubectl logs --since=48h podname > 24Logs.txt
Then you can easily check the logs for specific time within last 48 hours.
1: yes, you can tail or filter by date.
As easy as running kubectl logs --help
Options:
-c, --container='': Print the logs of this container
-f, --follow=false: Specify if the logs should be streamed.
--include-extended-apis=true: If true, include definitions of new APIs via calls to the API server. [default true]
--interactive=false: If true, prompt the user for input when required.
--limit-bytes=0: Maximum bytes of logs to return. Defaults to no limit.
--pod-running-timeout=20s: The length of time (like 5s, 2m, or 3h, higher than zero) to wait until at least one
pod is running
-p, --previous=false: If true, print the logs for the previous instance of the container in a pod if it exists.
-l, --selector='': Selector (label query) to filter on.
--since=0s: Only return logs newer than a relative duration like 5s, 2m, or 3h. Defaults to all logs. Only one of
since-time / since may be used.
--since-time='': Only return logs after a specific date (RFC3339). Defaults to all logs. Only one of since-time /
since may be used.
--tail=-1: Lines of recent log file to display. Defaults to -1 with no selector, showing all log lines otherwise
10, if a selector is provided.
--timestamps=false: Include timestamps on each line in the log output2: Docker stores the container logs in host in the path /var/lib/docker/containers/{ContainerId} so you could copy/truncate the logs directly.
That won't have any impact in the container or the pod.