expand node-level log rotation options #14929
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Development docs for logging have moved to sig-instrumentation.
Removes references to the deprecated `/cluster` scripts from the logging documentation, adding in sectional breakdown for log rotation setup using either `logrotate` or configuring the Docker container runtime logging driver. Related to k/k Issue #78995.
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Deploy preview for kubernetes-io-master-staging ready! Built with commit 484ea38 https://deploy-preview-14929--kubernetes-io-master-staging.netlify.com |
| ### Use container runtime logging rotation | ||
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| You can also set up a container runtime to rotate an application's logs | ||
| automatically, e.g. by using Docker's `log-opt`. |
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possible edit, remove: , e.g.
| `/etc/docker/daemon.json`: | ||
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| ``` | ||
| { |
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nit: add json as code block language
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| {{< note >}} | ||
| Currently, if some external system has performed the rotation, | ||
| only the contents of the latest log file will be available through | ||
| `kubectl logs`. E.g. if there's a 10MB file, `logrotate` performs | ||
| `kubectl logs`. e.g. if there's a 10MB file, `logrotate` performs | ||
| the rotation and there are two files, one 10MB in size and one empty, |
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Would you substitute e.g. with For example, if there is a ...
Do you know why an empty file is created in this case? The example is not completely clear to me, unless the empty file is created after a max-size was reached and subsequently logrotate performed?
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| {{< note >}} | ||
| By default, Kubernetes will store a Pod's logs in | ||
| `/var/log/pods/{NAMESPACE_NAME_UID}/{POD}.log`. Kubernetes Services, in |
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possible edit: By default, Kubernetes stores Pod log files in /var/log/pods/{NAMESPACE_NAME_UID}/{POD}.log, and Service log files in /var/log/{SERVICE_NAME}.log.
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I like the fixup aspect of this change request.
However, I am wary about adding a new section Use container runtime logging rotation
It would be OK to describe that in a Task page; perhaps inside /docs/tasks/administer-cluster/cluster-management/?
I'm also concerned that the revised page isn't telling the whole story. There's more to how to manage and rotate Pods' logs. The documentation should at some point mention kubelet flags --container-log-max-size and --container-log-max-files. This could be either in a Task page or in a page that explains logging conceptually (or maybe both).
It's good to let cluster operators know about options. For example if there were a Task page on this it could have tabs for different options. Select one tab and learn about using logrotate via a DaemonSet; another tab can explain logrotate with no DaemonSet, and a third tab can cover CRI container log rotation.
Lots of cluster operators use Docker to run containers and Docker doesn't seem to work with CRIContainerLogRotation. With that in mind the logrotate advice is relevant and I like the idea of making sure that advice is accurate as well.
@jaypipes, would you be willing to narrow the scope of this PR and then follow it up with more improvements? I'm also keen to hear your thoughts.
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Gonna close this out and submit the link fix separately. I'll do a separate PR that carves out a Task page for logging that has the updated information and removes the references to |
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Separate link fix here: #15270 |
Removes references to the deprecated
/clusterscripts from the loggingdocumentation, adding in sectional breakdown for log rotation setup
using either
logrotateor configuring the Docker container runtimelogging driver.
Related to k/k Issue #78995.