ops: wire monitoring stack to traefik metrics

monitoring/docker-compose.yml

@@ -13,9 +13,6 @@ services:
       - prometheus_data:/prometheus
     networks:
       - monitoring_net
-    extra_hosts:
-      # Lets Prometheus scrape host-published Traefik metrics on Unraid.
-      - host.docker.internal:host-gateway
     expose:
       - "9090"
     security_opt:
@@ -101,6 +98,9 @@ services:
     restart: "no"
     environment:
       GF_SECURITY_ADMIN_PASSWORD: ${GF_SECURITY_ADMIN_PASSWORD}
+    dns:
+      - 1.1.1.1
+      - 8.8.8.8
     networks:
       - monitoring_net
       - frontend_net
@@ -137,6 +137,22 @@ services:
                 body = response.read()
                 return json.loads(body.decode() or "{}") if body else {}
 
+        def import_dashboard(payload, dashboard_id):
+            for attempt in range(1, 7):
+                try:
+                    return request("/api/dashboards/import", payload)
+                except urllib.error.HTTPError as exc:
+                    body = exc.read().decode(errors="replace")[:300]
+                    if attempt == 6:
+                        raise RuntimeError(f"Dashboard {dashboard_id} import failed: {exc.code} {body}") from exc
+                    print(f"Dashboard {dashboard_id} import attempt {attempt} failed: HTTP {exc.code} {body}")
+                    time.sleep(5)
+                except Exception as exc:
+                    if attempt == 6:
+                        raise
+                    print(f"Dashboard {dashboard_id} import attempt {attempt} failed: {exc}")
+                    time.sleep(5)
+
         for _ in range(60):
             try:
                 request("/api/health", timeout=5)
@@ -153,12 +169,20 @@ services:
             (13639, "Loki"),
         ]
 
+        def fetch_dashboard(dashboard_id):
+            url = f"https://grafana.com/api/dashboards/{dashboard_id}/revisions/latest/download"
+            for attempt in range(1, 7):
+                try:
+                    with urllib.request.urlopen(url, timeout=30) as response:
+                        return json.loads(response.read().decode())
+                except Exception as exc:
+                    if attempt == 6:
+                        raise
+                    print(f"Dashboard {dashboard_id} download attempt {attempt} failed: {exc}")
+                    time.sleep(5)
+
         for dashboard_id, default_datasource in dashboards:
-            with urllib.request.urlopen(
-                f"https://grafana.com/api/dashboards/{dashboard_id}/revisions/latest/download",
-                timeout=30,
-            ) as response:
-                dashboard = json.loads(response.read().decode())
+            dashboard = fetch_dashboard(dashboard_id)
 
             inputs = []
             for item in dashboard.get("__inputs", []):
@@ -171,11 +195,11 @@ services:
                     "value": value,
                 })
 
-            request("/api/dashboards/import", {
+            import_dashboard({
                 "dashboard": dashboard,
                 "overwrite": True,
                 "inputs": inputs,
-            })
+            }, dashboard_id)
             print(f"Imported Grafana dashboard {dashboard_id}")
         PY
 
@@ -191,7 +215,7 @@ services:
     volumes:
       - /proc:/host/proc:ro
       - /sys:/host/sys:ro
-      - /:/rootfs:ro,rslave
+      - /:/rootfs:ro
     networks:
       - monitoring_net
     expose: