diff --git a/selfdrive/manager/manager.py b/selfdrive/manager/manager.py
index 0bcd686d70..b8ed6db814 100755
--- a/selfdrive/manager/manager.py
+++ b/selfdrive/manager/manager.py
@@ -155,6 +155,12 @@ def manager_init() -> None:
   else:
     serial = params.get("HardwareSerial")
     raise Exception(f"Registration failed for device {serial}")
+  if params.get("HardwareSerial") is None:
+    try:
+      serial = HARDWARE.get_serial()
+      params.put("HardwareSerial", serial)
+    except Exception:
+      cloudlog.exception("Error getting serial for device")
   os.environ['DONGLE_ID'] = dongle_id  # Needed for swaglog
 
   if not is_dirty():
diff --git a/selfdrive/sentry.py b/selfdrive/sentry.py
index 43bd9101cc..7dfdf81b53 100644
--- a/selfdrive/sentry.py
+++ b/selfdrive/sentry.py
@@ -97,7 +97,9 @@ def get_properties() -> Tuple[str, str]:
   params = Params()
   dongle_id = params.get("DongleId", encoding='utf-8')
   if dongle_id in (None, UNREGISTERED_DONGLE_ID):
-    dongle_id = UNREGISTERED_DONGLE_ID
+    hardware_serial = params.get("HardwareSerial", encoding='utf-8')
+    hardware_serial = "" if hardware_serial is None else hardware_serial
+    dongle_id = UNREGISTERED_DONGLE_ID + hardware_serial
   gitname = params.get("GithubUsername", encoding='utf-8')
   if gitname is None:
     gitname = ""