node_exporter on all three hosts (port 9100, ZT-only). Prometheus
server scrapes via the clan ZT IPv6s. Alertmanager routes alerts to
@HarakatBot (chat 66070351); critical repeats every 1h, others 4h.
Starter rule: HostDown when up==0 for 5m. Grafana on :3000 over ZT,
provisioned with the local Prometheus as default datasource.
Manual secrets on sunken-ship: /etc/alertmanager/telegram-token and
/etc/grafana/secret-key.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
