modified: ../README.md

modified:   __init__.py
modified:   catalog_zone_manager.py
modified:   dns_server.py
modified:   notify_handler.py
Adding serial to notify messages to allow client to determine state.

netbox_dns_bridge/notify_handler.py

@@ -3,16 +3,18 @@ import dns.name
 import dns.opcode
 import dns.query
 import dns.rdatatype
+import dns.rdataclass
+import dns.rrset
 import dns.tsig
 from django.conf import settings
 from django.utils import timezone
 from django.db import close_old_connections, OperationalError
 from netbox.jobs import JobRunner
-from netbox_dns.models import View, Zone
+from netbox_dns.models import View, Zone, Record
 from .logger import get_logger
-from .models import SeenTransferClients
+from .models import SeenTransferClients, IntegerKeyValueSetting
 
-logger = get_logger(__name__)
+LOGGER = get_logger(__name__)
 SETTINGS = settings.PLUGINS_CONFIG["netbox_dns_bridge"]
 
 
@@ -46,41 +48,93 @@ class SendDNSNotify(JobRunner):
         return dns.tsig.Key(name=key_name, secret=secret, algorithm=algorithm)
 
     def run(self, *args, **kwargs):
+        notify_over_tcp = SETTINGS.get("notify_over_tcp", False)
         view_name = kwargs["view_name"]
-        zone_name = kwargs["zone_name"]
 
         try:
+            catz_serial = IntegerKeyValueSetting.objects.get(key="catalog-zone-soa-serial").value
+
+            zones = [
+                (kwargs["zone_name"], kwargs["soa_serial"]),
+                ("catz",              catz_serial),
+                (f"{view_name}.catz", catz_serial)
+            ]
+
             view = View.objects.get(name=view_name)
             tsig_key = self._load_tsig_key(view_name)
             cutoff_hours = SETTINGS.get("notify_client_alive_threshold_hours", 24)
             seen_cutoff = timezone.now() - timezone.timedelta(hours=cutoff_hours)
+
             clients = SeenTransferClients.objects.filter(
                 view=view, last_seen__gte=seen_cutoff
             )
 
-            for name in (zone_name, "catz", f"{view_name}.catz"):
-                msg = dns.message.make_query(name, dns.rdatatype.SOA)
+            for zone_name, soa_serial in zones:
+                msg = dns.message.make_query(zone_name, dns.rdatatype.SOA)
                 msg.flags = 0
                 msg.set_opcode(dns.opcode.NOTIFY)
+
+                soa_rdata = dns.rdata.from_text(
+                    dns.rdataclass.IN,
+                    dns.rdatatype.SOA,
+                    f"invalid invalid {soa_serial} 60 10 1209600 0",
+                )
+                soa_rrset = dns.rrset.from_rdata(
+                    dns.name.from_text(zone_name, dns.name.root), 0, soa_rdata
+                )
+                msg.authority.append(soa_rrset)
                 msg.use_tsig(keyring={tsig_key.name: tsig_key}, keyname=tsig_key.name)
 
                 for client in clients:
                     try:
-                        dns.query.udp(msg, client.source_ip, port=5355, timeout=2)
-                        self.logger.info(
-                            f"NOTIFY sent to {client.source_ip} for zone {name}"
+                        if notify_over_tcp:
+                            LOGGER.info("Sending over TCP")
+                            dns.query.tcp(msg, client.source_ip, timeout=2)
+                        else:
+                            LOGGER.info("Sending over UDP")
+                            dns.query.udp(msg, client.source_ip, timeout=2)
+
+                        LOGGER.info(
+                            f"NOTIFY sent to {client.source_ip} for zone {zone_name}"
                         )
                     except Exception as e:
-                        self.logger.error(
-                            f"NOTIFY failed for {client.source_ip} zone {name}: {e}"
+                        LOGGER.error(
+                            f"NOTIFY failed for {client.source_ip} zone {zone_name}: {e}"
                         )
+
+        except IntegerKeyValueSetting.DoesNotExist as e:
+            LOGGER.error(f"Failed to get catalog zone serial: {e}")
+
         except OperationalError as e:
-            self.logger.error(f"NOTIFY failed due to unexpected error: {e}")
+            LOGGER.error(f"NOTIFY failed due to unexpected error: {e}")
             close_old_connections()
 
 
 def schedule(zone: Zone):
+    try:
+        soa_record = Record.objects.filter(
+            zone=zone, type="SOA", active=True
+        ).first()
+        if soa_record is None:
+            LOGGER.error(
+                f"Zone {zone.name} has no active SOA record — skipping NOTIFY"
+            )
+            return
+
+        soa_serial = int(soa_record.value.split()[2])
+
+    except OperationalError as e:
+        LOGGER.error(f"DB ERROR while fetching SOA for zone {zone.name}: {e}")
+        close_old_connections()
+        return
+    except (ValueError, IndexError) as e:
+        LOGGER.error(
+            f"Failed to parse SOA serial for zone {zone.name}: {e}"
+        )
+        return
+
     SendDNSNotify.enqueue(
         zone_name=zone.name,
         view_name=zone.view.name,
+        soa_serial=soa_serial,
     )