Grafana 13 externalised its core data sources; nixpkgs no longer bundles
the Elasticsearch datasource, so every DMARC panel failed with "Plugin not
registered". Load the official Grafana-signed elasticsearch plugin via
declarativePlugins, pin the dmarc-ag/dmarc-fo datasource UIDs (Grafana 11+
resolves datasource template variables by UID, not name), and clear stale
uid-less records left by an earlier deploy.
Deliver cnx.email DMARC aggregate/forensic reports to a dedicated dmarc@cnx.email
mailbox on mx1 and analyze them with parsedmarc on control, storing parsed
reports in a local loopback Elasticsearch and visualizing via the auto-provisioned
Grafana dashboard. parsedmarc fetches the mailbox over IMAPS across the mesh
(mx1.cnx.email pinned to its mesh address so TLS still validates), using a shared
mail-dmarc-cred clan var so mx1's mailserver and control see the same password.
Berwn