fix for qos failures for master branch due to backplane changes

tests/common/devices/sonic.py

@@ -27,7 +27,6 @@
 from tests.common import constants
 
 logger = logging.getLogger(__name__)
-
 PROCESS_TO_CONTAINER_MAP = {
     "orchagent": "swss",
     "syncd": "syncd"
@@ -2405,6 +2404,17 @@ def is_backend_portchannel(self, port_channel, mg_facts):
     def is_backend_port(self, port, mg_facts):
         return True if "Ethernet-BP" in port else False
 
+    def get_backplane_ports(self):
+        # get current interface data from config_db.json
+        config_facts = self.config_facts(host=self.hostname, source='running', verbose=False)['ansible_facts']
+        config_db_ports = config_facts["PORT"]
+        # Build set of Ethernet ports with 18.x.202.0/31 IPs to exclude
+        excluded_ports = set()
+        for port, val in config_db_ports.items():
+            if "role" in val:
+                excluded_ports.add(port)
+        return excluded_ports
+
     def active_ip_interfaces(self, ip_ifs, tbinfo, ns_arg=DEFAULT_NAMESPACE, intf_num="all"):
         """
         Return a dict of active IP (Ethernet or PortChannel) interfaces, with

tests/qos/qos_sai_base.py

@@ -996,16 +996,23 @@ def dutConfig(
         dst_dut = get_src_dst_asic_and_duts['dst_dut']
         src_mgFacts = src_dut.get_extended_minigraph_facts(tbinfo)
         topo = tbinfo["topo"]["name"]
-        src_mgFacts['minigraph_ptf_indices'] = {
+
+        # Build a set of Ethernet ports to exclude (with 18.x.202.0/31 IPs)
+        excluded_ports = set()
+        excluded_ports.update(duthosts[0].get_backplane_ports())
+        # Filter minigraph_ptf_indices to exclude dynamic ports
+        src_mgFacts["minigraph_ptf_indices"] = {
             key: value
-            for key, value in src_mgFacts['minigraph_ptf_indices'].items()
-            if not key.startswith("Ethernet-BP")
-            }
-        src_mgFacts['minigraph_ports'] = {
+            for key, value in src_mgFacts["minigraph_ptf_indices"].items()
+            if key not in excluded_ports
+        }
+
+        # Filter minigraph_ports to exclude dynamic ports
+        src_mgFacts["minigraph_ports"] = {
             key: value
-            for key, value in src_mgFacts['minigraph_ports'].items()
-            if not key.startswith("Ethernet-BP")
-            }
+            for key, value in src_mgFacts["minigraph_ports"].items()
+            if key not in excluded_ports
+        }
 
         # LAG ports in T1 TOPO need to be removed in Mellanox devices
         if topo in self.SUPPORTED_T0_TOPOS or (topo in self.SUPPORTED_PTF_TOPOS and isMellanoxDevice(src_dut)):