Add alert for wireguard handshake

services/monitoring/prometheus.nix

@@ -218,6 +218,16 @@
                 annotations:
                   summary: SMART Wearout Indicator (instance {{ $labels.instance }})
                   description: "Device is wearing out on {{ $labels.instance }} drive {{ $labels.device }})\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"
+          - name: wireguard_rules
+            rules:
+              - alert: WireguardHandshake
+                expr: (time() - wireguard_latest_handshake_seconds{instance="http-proxy.home.2rjus.net:9586",interface="wg0",public_key="32Rb13wExcy8uI92JTnFdiOfkv0mlQ6f181WA741DHs="}) > 300
+                for: 1m
+                labels:
+                  severity: warning
+                annotations:
+                  summary: "Wireguard handshake timeout on {{ $labels.instance }}"
+                  description: "Wireguard handshake timeout on {{ $labels.instance }} for more than 1 minutes."
       ''
     ];