1 files changed, 19 insertions, 8 deletions
diff --git a/resources/traffic_scripts/span_check.py b/resources/traffic_scripts/span_check.py
index c7ca8a7374..cbf65d3aaf 100755
--- a/resources/traffic_scripts/span_check.py
+++ b/resources/traffic_scripts/span_check.py
@@ -21,7 +21,7 @@ import sys
 import ipaddress
 
 from scapy.layers.inet import IP, ICMP, ARP
-from scapy.layers.inet6 import IPv6, ICMPv6EchoRequest, ICMPv6EchoReply
+from scapy.layers.inet6 import IPv6, ICMPv6EchoRequest, ICMPv6ND_NS
 from scapy.layers.l2 import Ether
 
 from resources.libraries.python.PacketVerifier import RxQueue, TxQueue, auto_pad
@@ -64,8 +64,8 @@ def main():
     """Send a simple L2 or ICMP packet from one TG interface to DUT, then
     receive a copy of the packet on the second TG interface, and a copy of
     the ICMP reply."""
-    args = TrafficScriptArg(
-        ['tg_src_mac', 'src_ip', 'dst_ip', 'dut_if1_mac', 'ptype'])
+    args = TrafficScriptArg(['tg_src_mac', 'src_ip', 'dst_ip', 'dut_if1_mac',
+                             'ptype'])
 
     src_mac = args.get_arg('tg_src_mac')
     dst_mac = args.get_arg('dut_if1_mac')
@@ -104,11 +104,20 @@ def main():
 
     txq.send(pkt_raw)
     sent.append(auto_pad(pkt_raw))
-    ether = rxq_mirrored.recv(2)
 
     # Receive copy of Rx packet.
-    if ether is None:
-        raise RuntimeError("Rx timeout of mirrored Rx packet")
+    while True:
+        ether = rxq_mirrored.recv(2)
+        if ether is None:
+            raise RuntimeError("Rx timeout of mirrored Rx packet")
+
+        if ether.haslayer(ICMPv6ND_NS):
+            # read another packet in the queue if the current one is ICMPv6ND_NS
+            continue
+        else:
+            # otherwise process the current packet
+            break
+
     pkt = auto_pad(pkt_raw)
     if str(ether) != str(pkt):
         print("Mirrored Rx packet doesn't match the original Rx packet.")
@@ -148,15 +157,17 @@ def main():
 
     # Receive reply on TG Tx port.
     ether_repl = rxq_tx.recv(2, sent)
+
     if ether_repl is None:
         raise RuntimeError("Reply not received on TG Tx port.")
-    else:
-        print("Reply received on TG Tx port.\n")
+
+    print("Reply received on TG Tx port.\n")
 
     # Receive copy of Tx packet.
     ether = rxq_mirrored.recv(2)
     if ether is None:
         raise RuntimeError("Rx timeout of mirrored Tx packet")
+
     if str(ether) != str(ether_repl):
         print("Mirrored Tx packet doesn't match the received Tx packet.")
         if ether.src != ether_repl.src or ether.dst != ether_repl.dst: