diff --git a/sec-beidou-rtcm/src/main/java/com/imdroid/sideslope/rtkcluster/GroupRtkScheduler.java b/sec-beidou-rtcm/src/main/java/com/imdroid/sideslope/rtkcluster/GroupRtkScheduler.java
index b7a67354..ed02cf98 100644
--- a/sec-beidou-rtcm/src/main/java/com/imdroid/sideslope/rtkcluster/GroupRtkScheduler.java
+++ b/sec-beidou-rtcm/src/main/java/com/imdroid/sideslope/rtkcluster/GroupRtkScheduler.java
@@ -37,6 +37,7 @@ public class GroupRtkScheduler {
         final Deque<String> outRing = new ArrayDeque<>(1024);
         Process process;
         Thread readerThread;
+        Endpoint endpoint;
         synchronized void addOut(String line) {
             if (outRing.size() >= 500) outRing.pollFirst();
             outRing.addLast(line);
@@ -64,10 +65,20 @@ public class GroupRtkScheduler {
                 resp.put("pid", rt.pid); resp.put("state", rt.state);
                 return resp;
             }
-            // Build a synthetic profile using group configuration
+            // Ensure local endpoint for capturing OUT stream
+            if (rt.endpoint == null) {
+                rt.endpoint = new Endpoint();
+                rt.endpoint.start();
+            }
+            // Build a synthetic profile using group configuration + local OUT endpoints
             RtkrcvProfile profile = new RtkrcvProfile();
             profile.setDeviceId("group-" + groupId);
             profile.setGroupId(groupId);
+            String epPath = "127.0.0.1:" + rt.endpoint.getPort();
+            profile.setOutstr1Path(epPath);
+            profile.setOutstr2Path(epPath);
+            // also set inpstr1 to same endpoint to avoid dead tcpcli
+            profile.setInpstr1Path(epPath);
             Path conf = configService.generateConfig(profile);
             rt.confPath = conf.toString();
             ProcessBuilder pb = new ProcessBuilder(rtkBinary, "-nc", "-o", conf.toString());
@@ -104,6 +115,7 @@ public class GroupRtkScheduler {
             boolean exited = rt.process.waitFor(3, java.util.concurrent.TimeUnit.SECONDS);
             if (!exited) rt.process.destroyForcibly();
             rt.state = "stopped";
+            if (rt.endpoint != null) { rt.endpoint.close(); rt.endpoint = null; }
             resp.put("code", 0);
         } catch (Exception e) {
             resp.put("code", 1); resp.put("msg", e.getMessage());
@@ -191,3 +203,73 @@ public class GroupRtkScheduler {
         return null;
     }
 }
+
+class Endpoint {
+    private static final org.slf4j.Logger LOG = org.slf4j.LoggerFactory.getLogger(Endpoint.class);
+    private java.net.ServerSocket server;
+    private Thread acceptThread;
+    private final java.util.Set<java.net.Socket> sockets = java.util.Collections.newSetFromMap(new java.util.concurrent.ConcurrentHashMap<>());
+    private volatile boolean running = false;
+    private int port;
+    private final java.util.concurrent.ExecutorService exec = java.util.concurrent.Executors.newCachedThreadPool(r -> {
+        Thread t = new Thread(r, "rtk-group-ep"); t.setDaemon(true); return t; });
+
+    void start() throws IOException {
+        server = new java.net.ServerSocket(0, 50, java.net.InetAddress.getByName("127.0.0.1"));
+        port = server.getLocalPort();
+        running = true;
+        acceptThread = new Thread(this::acceptLoop, "rtk-ep-accept-"+port);
+        acceptThread.setDaemon(true);
+        acceptThread.start();
+        LOG.info("[endpoint] listening 127.0.0.1:{}", port);
+    }
+
+    int getPort() { return port; }
+
+    private void acceptLoop() {
+        while (running) {
+            try {
+                java.net.Socket s = server.accept();
+                sockets.add(s);
+                handle(s);
+            } catch (IOException e) {
+                if (running) LOG.warn("[endpoint] accept error: {}", e.getMessage());
+            }
+        }
+    }
+
+    private void handle(java.net.Socket s) {
+        exec.submit(() -> {
+            try {
+                s.setTcpNoDelay(true);
+                s.setKeepAlive(true);
+                InputStream in = s.getInputStream();
+                OutputStream os = s.getOutputStream();
+                byte[] buf = new byte[2048];
+                int read = in.read(buf);
+                if (read > 0) {
+                    String head = new String(buf, 0, Math.min(read, 256), StandardCharsets.US_ASCII);
+                    if (head.startsWith("GET ") || head.contains("RTKLIB/")) {
+                        String resp = head.contains("HTTP") ? "HTTP/1.1 200 OK\r\nConnection: keep-alive\r\n\r\n" : "ICY 200 OK\r\n\r\n";
+                        os.write(resp.getBytes(StandardCharsets.US_ASCII)); os.flush();
+                    }
+                    // Log first chunk
+                    LOG.info("[endpoint:{}] {}", port, head.replaceAll("\n","\\n"));
+                }
+                // Continue pumping to dev-null while connected
+                while (read != -1) { read = in.read(buf); }
+            } catch (IOException ignore) {
+            } finally {
+                sockets.remove(s);
+                try { s.close(); } catch (IOException ignore) {}
+            }
+        });
+    }
+
+    void close() {
+        running = false;
+        try { if (server != null) server.close(); } catch (IOException ignore) {}
+        for (java.net.Socket s : sockets) { try { s.close(); } catch (IOException ignore) {} }
+        exec.shutdownNow();
+    }
+}