DNSResolutionProbeFailed and DNSSECProbeFailed fire when an SOA or
DNSKEY probe to a public nameserver address stays down for 5m. The CNX
DNS dashboard gains a "DNS probes (outside-in)" row: per-zone/server
status table, probe success, and probe latency.
Surfaces vmalert's firing ALERTS series as a table at the top of the dashboard,
so the minimal-delivery alerts are visible at a glance. Existing panels shift
down by one row.
control runs VictoriaMetrics (loopback) and Grafana; every machine exports
node metrics and the nameservers export Knot stats (mod-stats + knot-exporter).
Scraping and the Grafana UI ride the ZeroTier mesh only, scoped by nftables to
the mesh /88; the public side stays closed by the Hetzner cloud firewall. The
provisioned DNS dashboard includes a per-zone SOA serial table to catch
primary/secondary drift. ZeroTier ULAs are centralised in mesh-hosts.nix.
Berwn