Module graceful shutdown support

data/debian/rules

@@ -20,5 +20,6 @@ override_dh_installsystemd:
 	dh_installsystemd --no-start --name=procdockerstatsd
 	dh_installsystemd --no-start --name=determine-reboot-cause
 	dh_installsystemd --no-start --name=process-reboot-cause
+	dh_installsystemd --no-start --name=gnoi-shutdown
 	dh_installsystemd $(HOST_SERVICE_OPTS) --name=sonic-hostservice
 

data/debian/sonic-host-services-data.gnoi-shutdown.service

@@ -0,0 +1,16 @@
+[Unit]
+Description=gNOI based DPU Graceful Shutdown Daemon
+Requires=database.service
+Wants=network-online.target
+After=network-online.target database.service
+
+[Service]
+Type=simple
+ExecStartPre=/usr/bin/python3 /usr/local/bin/check_platform.py
+ExecStartPre=/bin/bash /usr/local/bin/wait-for-sonic-core.sh
+ExecStart=/usr/bin/python3 /usr/local/bin/gnoi_shutdown_daemon.py
+Restart=always
+RestartSec=5
+
+[Install]
+WantedBy=multi-user.target

scripts/check_platform.py

@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+"""
+Check if the current platform is a SmartSwitch NPU (not DPU).
+Exit 0 if SmartSwitch NPU, exit 1 otherwise.
+"""
+import sys
+import subprocess
+
+def main():
+    try:
+        # Get subtype from config
+        result = subprocess.run(
+            ['sonic-cfggen', '-d', '-v', 'DEVICE_METADATA.localhost.subtype'],
+            capture_output=True,
+            text=True,
+            timeout=5
+        )
+        if result.returncode != 0:
+            # Optionally print error for debugging
+            print(f"Error: sonic-cfggen failed with return code {result.returncode}", file=sys.stderr)
+            print(result.stderr, file=sys.stderr)
+            sys.exit(1)
+        subtype = result.stdout.strip()
+
+        # Check if DPU
+        try:
+            from utilities_common.chassis import is_dpu
+            is_dpu_platform = is_dpu()
+        except Exception:
+            is_dpu_platform = False
+
+        # Check if SmartSwitch NPU (not DPU)
+        if subtype == "SmartSwitch" and not is_dpu_platform:
+            sys.exit(0)
+        else:
+            sys.exit(1)
+    except Exception:
+        sys.exit(1)
+
+if __name__ == "__main__":
+    main()