stop sniffer

backend/src/utilities/packet_tracker.py

@@ -55,6 +55,30 @@ class PacketTracker:
         self._stop_event.set()
         self._thread.join(timeout=settings.packet_tracker_stop_join_timeout_seconds)
 
+    def discard_entries_for_ifaces(self, ifaces: List[str]) -> int:
+        """Drop in-memory entries that belong to interfaces no longer being sniffed."""
+        targets = {iface for iface in ifaces if iface}
+        if not targets:
+            return 0
+
+        removed = 0
+        with self._lock:
+            for correlation_key in list(self._entries.keys()):
+                payload = self._entries[correlation_key]["payload"]
+                related_ifaces = {
+                    payload.get("ingress_if"),
+                    payload.get("egress_if"),
+                    payload.get("capture_iface"),
+                }
+                telemetry_metadata = payload.get("telemetry_metadata") or {}
+                if isinstance(telemetry_metadata, dict):
+                    related_ifaces.add(telemetry_metadata.get("iface"))
+
+                if related_ifaces & targets:
+                    self._entries.pop(correlation_key, None)
+                    removed += 1
+        return removed
+
     def observe_packet(self, pkt_info: Dict[str, Any]) -> str:
         """Merge parsed packet information into a pending packet entry."""
         now_ts = time.time()