The Configure Monitoring page has a link to "Munin Diagnostics":

SEE ALSO
The Munin Diagnostics section on the Diagnostic and Troubleshooting Guide page.

However, the Monitoring Troubleshooting page doesn't actually have a #munin-diagnostics anchor - but there is one however for #munin.

We should probably point the URL to a working anchor, otherwise when the user clicks on the link, they're taken to the top of a very long page.