This plugin adds a CLI command to watch Jenkins system log messages in real time. This is useful if you wish to monitor activity from a shell. You can get detailed logs from a particular component.

For detailed usage information, go to https://<jenkins>/cli/command/tail-log after installation.

You can also choose to send system logs to the Jenkins controller’s standard error stream. While Jenkins sends INFO and above by default, this plugin allows you to configure more detailed messages from particular components of interest.

From the GUI, check Fine logging to standard error in system configuration. Using JCasC (configuration-as-code), use the following format:

unclassified:
  stderrLog:
    targets:
    - name: io.jenkins.plugins.whatever
      level: FINE

As a bonus, this will stream messages in the selected components printed by agents as well, which are otherwise very tricky to collect.

Viewing the resulting logs is a separate matter. On Kubernetes, you can use for example kubectl logs -f $podname, or try kubectl krew install tail or kubectl krew install stern for richer options.