[PMM 3.1.0] Built-in Dashboards Not Showing Metrics in PMM3

Hello Percona Support Team,

We are currently using PMM3 in our production environment, and I’ve run into an issue after attempting to route Grafana alerts through an internal proxy.

  1. Initially, we were unable to send Slack notifications via the built-in grafana-alertmanager due to internal network restrictions (outbound traffic blocked by proxy).
  2. As a workaround, we deployed an external Alertmanager Docker container and registered it as a data source in PMM Grafana.
  3. The custom alert rules and messaging pipeline are now functioning correctly, and Slack notifications are being delivered as expected.
  4. Additionally, all of our custom dashboards are working fine — metrics appear correctly because they explicitly use the Metrics data source.
  5. However, the built-in dashboards that come with PMM3 do not show any metrics. They appear blank.
  6. Upon investigation, I found that these built-in dashboards are using -- Grafana -- as their data source, which appears to be linked to synthetic/fake data.
  7. I’m not sure why the data source has changed for the built-in dashboards — this was not the case before. I tried:
  • Reverting to the previous configuration by disabling the external Alertmanager,
  • Re-selecting Grafana under “Contact Points → Choose Alertmanager”,
  • Even modifying container-mounted dashboard JSON files.None of these attempts resolved the issue.

Is there a supported way to restore or rebind the built-in dashboards so that they point to the correct Metrics data source again (instead of -- Grafana --)?

Any advice or documented method to recover this behavior would be greatly appreciated.
Thank you for your support.

[This is a built-in dashboards]