diff --git a/devapp/dev_types.py b/devapp/dev_types.py
index 8d721a3..2f5d680 100644
--- a/devapp/dev_types.py
+++ b/devapp/dev_types.py
@@ -61,6 +61,7 @@ class DLinkPort(BasePort):
 
 class DLinkDevice(DevBase, SNMPBaseWorker):
     has_attachable_to_subscriber = True
+    tech_code = 'dlink_sw'
     is_use_device_port = True
 
     def __init__(self, dev_instance):
@@ -201,6 +202,7 @@ class OLTDevice(DevBase, SNMPBaseWorker):
 
 class OnuDevice(DevBase, SNMPBaseWorker):
     has_attachable_to_subscriber = True
+    tech_code = 'bdcom_onu'
     is_use_device_port = False
 
     def __init__(self, dev_instance):
@@ -319,6 +321,7 @@ class EltexPort(BasePort):
 
 class EltexSwitch(DLinkDevice):
     has_attachable_to_subscriber = True
+    tech_code = 'eltex_sw'
     is_use_device_port = False
 
     @staticmethod
@@ -427,6 +430,8 @@ class Olt_ZTE_C320(OLTDevice):
 
 
 class ZteOnuDevice(OnuDevice):
+    tech_code = 'zte_onu'
+
     @staticmethod
     def description():
         return _('ZTE PON ONU')
diff --git a/devapp/onu_register.py b/devapp/onu_register.py
index 71b3f60..c3118b7 100644
--- a/devapp/onu_register.py
+++ b/devapp/onu_register.py
@@ -6,9 +6,19 @@ from subprocess import run
 def onu_register(devices: Iterable):
     with open('/etc/dhcp/macs.conf', 'w') as f:
         for dev in devices:
-            if dev.has_attachable_to_subscriber() and dev.mac_addr is not None:
-                f.write('subclass "%(code)s" "%(mac)s";\n' % {
-                    'code': dev.group.code,
-                    'mac': dev.mac_addr
+            if not dev.has_attachable_to_subscriber() or dev.mac_addr is None:
+                continue
+            group_code = dev.group.code
+            if not group_code:
+                continue
+            try:
+                mn = dev.get_manager_klass()
+                dev_code = mn.tech_code
+                f.write('subclass "%(group_code)s.%(dev_code)s" "%(mac)s";\n' % {
+                    'group_code': group_code,
+                    'mac': dev.mac_addr,
+                    'dev_code': dev_code
                 })
+            except TypeError:
+                continue
     run(('/usr/bin/sudo', 'systemctl', 'restart', 'isc-dhcp-server.service'))