Log to stdout / pebble

[gboutry]

Currently, debugging mysql-router errors is not straightforward.

We need to ask users to basically:

juju ssh --container mysql-router/0 bash
cd /var/log/mysqlrouter
ls -alh **/*.log
<find logs with more than 0 bytes>

While this process could be simplified with better commands, being able to just do kubectl logs -c mysql-router mysql-router-0 would be a much better experience.

cross posting from: canonical/mysql-k8s-operator#630

[syncronize-issues-to-jira]

Thank you for reporting your feedback to us!

The internal ticket has been created: https://warthogs.atlassian.net/browse/DPE-7655.

This message was autogenerated

[carlcsaposs-canonical]

cc @paulomach regarding log rotation & any approvals needed to diverge our vm/k8s log rotation

[gboutry]

as quickly discussed with @paulomach, this might be keeping the same process for log forwarding, but also adding stdout logging.

[carlcsaposs-canonical]

would the stdout/k8s logs also need to be rotated?

[gboutry]

It does not, container stdout gets logged into a kind of ringbuffer, so it would get automatically erased (I think it's around 100KB?)

[gboutry]

But this might get doubly logged into loki once observability is enabled?

[carlcsaposs-canonical]

It looks like the Kubernetes log rotation is configurable (https://kubernetes.io/docs/concepts/cluster-administration/logging/#log-rotation), which might be confusing from a UX perspective (since if a user is deploying the charm in an environment where the k8s logs are retained, our user documentation on how to configure log rotation will mislead them—and there will be multiple ways to set up logging & log rotation)

Although not sure if I'm correctly understanding how Kubernetes handles logs

[paulomach]

If we decide to stream logs to stdout and file, the stdout log rotation is not our responsibility.
The question boils down to how to enabled multiple log sinks.

[syncronize-issues-to-jira]

Thank you for reporting your feedback to us!

The internal ticket has been created: https://warthogs.atlassian.net/browse/DPE-8060.

This message was autogenerated