diff --git a/DOCUMENTACION.md b/DOCUMENTACION.md
index c1b5b79..a14d198 100644
--- a/DOCUMENTACION.md
+++ b/DOCUMENTACION.md
@@ -248,6 +248,7 @@ Ubicacion fisica o logica. Actualmente se muestra en la tarjeta.
 Por SSH se leen datos de solo lectura:
 
 - Temperatura CPU
+- Temperatura Top-Rack opcional desde archivo JSON escrito por Node-RED
 - Uso CPU
 - Uso RAM
 - Uso disco raiz `/`
@@ -262,6 +263,26 @@ Por SSH se leen datos de solo lectura:
 - Velocidad nominal si existe
 - Trafico RX/TX calculado entre scans
 
+### Temperatura Top-Rack
+
+Si una RPi tiene un sensor externo de temperatura del rack, Node-RED puede escribir la lectura en un archivo local del mismo equipo:
+
+```json
+{
+  "temperatureC": 23.7,
+  "sensor": "rack-top",
+  "updatedAt": "2026-06-05T21:12:18.997Z"
+}
+```
+
+En el configurador, coloca la ruta en el dispositivo que tiene el sensor:
+
+```text
+/home/yamaray/monitor-rpi/rack-temp.json
+```
+
+El backend lee ese archivo durante el mismo scan SSH y muestra el valor como `Temperatura Top-Rack` en la primera linea del dashboard.
+
 ## Clientes Activos
 
 El dashboard envia heartbeat al backend cuando esta visible.
diff --git a/config.example.json b/config.example.json
index 357849c..86a8d8f 100644
--- a/config.example.json
+++ b/config.example.json
@@ -41,6 +41,7 @@
       "password": "",
       "authMethod": "password",
       "privateKeyPath": "",
+      "rackTemperatureFile": "",
       "role": "Home Assistant Local",
       "port": 22,
       "id": "rpi5-ha-main",
@@ -55,6 +56,7 @@
       "password": "",
       "authMethod": "password",
       "privateKeyPath": "",
+      "rackTemperatureFile": "",
       "role": "Home Assistant Cabaña",
       "port": 22,
       "id": "rpi4-ha-second",
@@ -69,6 +71,7 @@
       "password": "",
       "authMethod": "password",
       "privateKeyPath": "",
+      "rackTemperatureFile": "",
       "role": "Docker",
       "port": 22,
       "id": "rpi5-jose-docker",
@@ -83,6 +86,7 @@
       "password": "",
       "authMethod": "password",
       "privateKeyPath": "",
+      "rackTemperatureFile": "",
       "role": "Docker - Daniel",
       "port": 22,
       "id": "rpi5-dani-docker",
@@ -97,6 +101,7 @@
       "password": "",
       "authMethod": "password",
       "privateKeyPath": "",
+      "rackTemperatureFile": "",
       "role": "nginx - wireguard ",
       "port": 22,
       "id": "rpi3-nginx",
@@ -111,6 +116,7 @@
       "password": "",
       "authMethod": "password",
       "privateKeyPath": "",
+      "rackTemperatureFile": "",
       "role": "MQTT - varios",
       "port": 22,
       "id": "rpi3-pi3home",
@@ -125,6 +131,7 @@
       "password": "",
       "authMethod": "password",
       "privateKeyPath": "",
+      "rackTemperatureFile": "/home/yamaray/monitor-rpi/rack-temp.json",
       "role": "Meshcore-Interface",
       "port": 22,
       "id": "rpi3-meshcore",
@@ -139,6 +146,7 @@
       "password": "",
       "authMethod": "password",
       "privateKeyPath": "",
+      "rackTemperatureFile": "",
       "role": "Reserva",
       "port": 22,
       "id": "rpi3-node-3",
diff --git a/config.html b/config.html
index 07ee4e5..e44602c 100644
--- a/config.html
+++ b/config.html
@@ -233,6 +233,7 @@
     .field-role { grid-column: span 3; }
     .field-model { grid-column: span 2; }
     .field-location { grid-column: span 2; }
+    .field-rack-temp { grid-column: span 4; }
     .field-host { grid-column: span 3; }
     .field-port { grid-column: span 1; }
     .field-username { grid-column: span 2; }
@@ -445,7 +446,7 @@
 
     @media (max-width: 1180px) {
       .device { grid-template-columns: repeat(6, minmax(0, 1fr)); align-items: start; }
-      .field-name, .field-role, .field-host, .password-credential { grid-column: span 3; }
+      .field-name, .field-role, .field-host, .password-credential, .field-rack-temp { grid-column: span 3; }
       .field-id, .field-model, .field-location, .field-username, .field-auth, .field-active, .field-delete { grid-column: span 2; }
       .field-port { grid-column: span 1; }
       .credential-note { grid-column: span 4; }
@@ -460,7 +461,7 @@
       .top-grid, .device { grid-template-columns: 1fr; }
       .field-active, .field-name, .field-id, .field-role, .field-model, .field-location,
       .field-host, .field-port, .field-username, .field-auth, .password-credential,
-      .credential-note, .field-delete { grid-column: span 1; }
+      .credential-note, .field-rack-temp, .field-delete { grid-column: span 1; }
       .threshold-row { grid-template-columns: 1fr; }
     }
   </style>
@@ -702,6 +703,9 @@
           <div class="credential-note">
             Metodo activo: <strong>${authMethod === "key" ? "Clave asimetrica: copiar clave publica del monitor en la RPi" : "Password"}</strong>
           </div>
+          <label class="field-rack-temp" title="Archivo opcional en este RPi con la temperatura del rack escrita por Node-RED. Si esta vacio, no se recoge temperatura Top-Rack desde este dispositivo.">Archivo temp rack
+            <input data-field="rackTemperatureFile" value="${device.rackTemperatureFile || ""}" placeholder="/home/yamaray/monitor-rpi/rack-temp.json">
+          </label>
           <label class="field-active" title="Si esta activo, este dispositivo se consulta por SSH. Si esta inactivo, se muestra deshabilitado y no se escanea.">Activo
             <input data-field="active" type="checkbox" ${device.active ? "checked" : ""}>
           </label>
@@ -848,6 +852,7 @@
         password: "",
         privateKeyPath: "",
         authMethod: "password",
+        rackTemperatureFile: "",
         model: "RPi 4",
         role: "",
         location: "Rack",
diff --git a/dashboard.html b/dashboard.html
index 24c0e5d..0e8fbfd 100644
--- a/dashboard.html
+++ b/dashboard.html
@@ -282,7 +282,7 @@
 
     .summary {
       display: grid;
-      grid-template-columns: repeat(5, minmax(130px, 1fr));
+      grid-template-columns: repeat(6, minmax(120px, 1fr));
       gap: 12px;
     }
 
@@ -981,6 +981,14 @@
               hottestSummaryClass(summary.hottest.value, temperatureThresholds)
             )
           : summaryItem("Mas caliente", "--"),
+        summary.rackTemperature
+          ? summaryItemWithNote(
+              "Temperatura Top-Rack",
+              `${summary.rackTemperature.temperatureC.toFixed(1)} C`,
+              summary.rackTemperature.deviceName || summary.rackTemperature.sensor || "",
+              hottestSummaryClass(summary.rackTemperature.temperatureC, temperatureThresholds)
+            )
+          : summaryItem("Temperatura Top-Rack", "--"),
         summaryItem("Total RPi configuradas", summary.total || 0),
         summaryItem("Alertas", summary.alerts?.length || 0, summary.alerts?.length > 0 ? "summary-hot" : "")
       ].join("");
diff --git a/docs.html b/docs.html
index b8369a1..828ac93 100644
--- a/docs.html
+++ b/docs.html
@@ -149,6 +149,16 @@ chmod 600 ~/.ssh/authorized_keys</code></pre>
     <pre><code>0 clientes visibles  -> idleScanIntervalSeconds
 1+ clientes visibles -> refreshIntervalSeconds</code></pre>
 
+    <h2>Temperatura Top-Rack</h2>
+    <p>Si una RPi tiene un sensor externo del rack, Node-RED puede escribir la lectura en un archivo JSON local.</p>
+    <pre><code>{
+  "temperatureC": 23.7,
+  "sensor": "rack-top",
+  "updatedAt": "2026-06-05T21:12:18.997Z"
+}</code></pre>
+    <p>En el configurador, en ese dispositivo, usa <code>Archivo temp rack</code> con una ruta como:</p>
+    <pre><code>/home/yamaray/monitor-rpi/rack-temp.json</code></pre>
+
     <h2>Docker</h2>
     <pre><code>cd /home/yamaray/docker/monitorRPi
 docker compose up -d --build</code></pre>
diff --git a/server.js b/server.js
index 84ffa07..78ec852 100644
--- a/server.js
+++ b/server.js
@@ -165,12 +165,22 @@ function mockMetrics(device) {
       speedMbps: device.model === "RPi 3" ? null : 1000,
       rxBytesPerSecond: Math.round(seededNumber(`${device.id}:rx`, 1200, 95000)),
       txBytesPerSecond: Math.round(seededNumber(`${device.id}:tx`, 700, 55000))
-    }
+    },
+    rackTemperature: device.rackTemperatureFile
+      ? {
+          temperatureC: Number(seededNumber(`${device.id}:rack-temp`, 25, 37).toFixed(1)),
+          sensor: "rack-top",
+          updatedAt: new Date().toISOString(),
+          ageSeconds: 0,
+          sourceFile: device.rackTemperatureFile
+        }
+      : null
   };
 }
 
 const REMOTE_METRICS_SCRIPT = `
 set +e
+rack_temperature_file="$RACK_TEMPERATURE_FILE"
 temp_raw="$(cat /sys/class/thermal/thermal_zone0/temp 2>/dev/null)"
 if [ -n "$temp_raw" ]; then
   temp_c="$(awk "BEGIN { printf \\"%.1f\\", $temp_raw / 1000 }")"
@@ -259,6 +269,27 @@ if [ "$ha_status" = "n/a" ] && [ "$docker_installed" = "1" ]; then
   fi
 fi
 
+rack_temperature_c=""
+rack_temperature_sensor=""
+rack_temperature_updated_at=""
+rack_temperature_age_seconds=""
+if [ -n "$rack_temperature_file" ] && [ -r "$rack_temperature_file" ]; then
+  rack_payload="$(cat "$rack_temperature_file" 2>/dev/null)"
+  rack_temperature_c="$(printf '%s' "$rack_payload" | awk -F '[:,}]' '/temperatureC/ { gsub(/[^0-9.\\-]/, "", $2); print $2; exit }')"
+  if [ -z "$rack_temperature_c" ]; then
+    rack_temperature_c="$(printf '%s' "$rack_payload" | awk 'NR==1 { gsub(/[^0-9.\\-]/, "", $1); print $1; exit }')"
+  fi
+  rack_temperature_sensor="$(printf '%s' "$rack_payload" | sed -n 's/.*"sensor"[[:space:]]*:[[:space:]]*"\\([^"]*\\)".*/\\1/p' | head -n 1)"
+  rack_temperature_updated_at="$(printf '%s' "$rack_payload" | sed -n 's/.*"updatedAt"[[:space:]]*:[[:space:]]*"\\([^"]*\\)".*/\\1/p' | head -n 1)"
+  if [ -n "$rack_temperature_updated_at" ]; then
+    rack_updated_epoch="$(date -d "$rack_temperature_updated_at" +%s 2>/dev/null)"
+    now_epoch="$(date +%s 2>/dev/null)"
+    if [ -n "$rack_updated_epoch" ] && [ -n "$now_epoch" ] && [ "$now_epoch" -ge "$rack_updated_epoch" ]; then
+      rack_temperature_age_seconds="$((now_epoch - rack_updated_epoch))"
+    fi
+  fi
+fi
+
 printf 'cpuTempC=%s\\n' "$temp_c"
 printf 'cpuCores=%s\\n' "$cpu_cores"
 printf 'cpuUsagePercent=%s\\n' "$cpu_usage"
@@ -283,6 +314,10 @@ printf 'dockerRunning=%s\\n' "$docker_running"
 printf 'dockerStopped=%s\\n' "$docker_stopped"
 printf 'dockerUnhealthy=%s\\n' "$docker_unhealthy"
 printf 'homeAssistantStatus=%s\\n' "$ha_status"
+printf 'rackTemperatureC=%s\\n' "$rack_temperature_c"
+printf 'rackTemperatureSensor=%s\\n' "$rack_temperature_sensor"
+printf 'rackTemperatureUpdatedAt=%s\\n' "$rack_temperature_updated_at"
+printf 'rackTemperatureAgeSeconds=%s\\n' "$rack_temperature_age_seconds"
 `;
 
 function parseKeyValueOutput(output) {
@@ -301,6 +336,10 @@ function toNumber(value, fallback = 0) {
   return Number.isFinite(parsed) ? parsed : fallback;
 }
 
+function shellQuote(value) {
+  return `'${String(value || "").replace(/'/g, `'\\''`)}'`;
+}
+
 function networkRates(device, values) {
   const sampleKey = device.id || `${device.host}:${device.port || 22}`;
   const now = Date.now();
@@ -333,9 +372,12 @@ function networkRates(device, values) {
   };
 }
 
-function runCommandWithInput(command, args, input, timeoutMs) {
+function runCommandWithInput(command, args, input, timeoutMs, env = {}) {
   return new Promise((resolve, reject) => {
-    const child = spawn(command, args, { stdio: ["pipe", "pipe", "pipe"] });
+    const child = spawn(command, args, {
+      stdio: ["pipe", "pipe", "pipe"],
+      env: { ...process.env, ...env }
+    });
     let stdout = "";
     let stderr = "";
     let settled = false;
@@ -428,9 +470,11 @@ async function sshMetrics(device) {
     ];
   }
 
-  const { stdout } = await runCommandWithInput(command, args, REMOTE_METRICS_SCRIPT, timeoutMs);
+  const remoteScript = `RACK_TEMPERATURE_FILE=${shellQuote(device.rackTemperatureFile || "")}\n${REMOTE_METRICS_SCRIPT}`;
+  const { stdout } = await runCommandWithInput(command, args, remoteScript, timeoutMs);
   const values = parseKeyValueOutput(stdout);
   const temp = toNumber(values.cpuTempC, 0);
+  const rackTemperatureC = toNumber(values.rackTemperatureC, null);
   const loadAverage = String(values.loadAverage || "")
     .split(/\s+/)
     .filter(Boolean)
@@ -460,7 +504,16 @@ async function sshMetrics(device) {
       detected: values.homeAssistantStatus && values.homeAssistantStatus !== "n/a",
       status: values.homeAssistantStatus || "n/a"
     },
-    network: networkRates(device, values)
+    network: networkRates(device, values),
+    rackTemperature: Number.isFinite(rackTemperatureC)
+      ? {
+          temperatureC: Number(rackTemperatureC.toFixed(1)),
+          sensor: values.rackTemperatureSensor || "",
+          updatedAt: values.rackTemperatureUpdatedAt || "",
+          ageSeconds: toNumber(values.rackTemperatureAgeSeconds, null),
+          sourceFile: device.rackTemperatureFile || ""
+        }
+      : null
   };
 }
 
@@ -520,6 +573,15 @@ function buildSummary(devices) {
     .filter((device) => device.metrics && Number.isFinite(device.metrics.cpuTempC))
     .map((device) => ({ name: device.name, value: device.metrics.cpuTempC }));
   const hottest = temps.sort((a, b) => b.value - a.value)[0] || null;
+  const rackTemperature = online
+    .map((device) => {
+      const rack = device.metrics?.rackTemperature;
+      return rack && Number.isFinite(rack.temperatureC)
+        ? { ...rack, deviceName: device.name }
+        : null;
+    })
+    .filter(Boolean)
+    .sort((a, b) => (a.ageSeconds ?? Number.MAX_SAFE_INTEGER) - (b.ageSeconds ?? Number.MAX_SAFE_INTEGER))[0] || null;
   const alerts = [];
 
   for (const device of devices) {
@@ -537,6 +599,7 @@ function buildSummary(devices) {
     online: online.length,
     offline: active.length - online.length,
     hottest,
+    rackTemperature,
     alerts
   };
 }