Fixed getting te result from HW2HW iperf test

Related-PROD: PROD-36943
Change-Id: I145ba8aea82e7b923a4821d42c73e3226e111d71
diff --git a/tests/test_hw2hw.py b/tests/test_hw2hw.py
index 38bd58d..78f37f7 100644
--- a/tests/test_hw2hw.py
+++ b/tests/test_hw2hw.py
@@ -98,7 +98,7 @@
         res2 = (b" ".join(result2.split()[-4:-2:])).decode('utf-8')
     else:
         iperf_utility = "iperf"
-        command2 = '{} -c {} -P {} -t {} -B {} | tail -n 1'.format(
+        command2 = '{} -c {} -P {} -t {} -B {} | tail -n 2 | grep SUM'.format(
             iperf_utility, nodes_info[1]["iperf_ip"], threads, iperf_time,
             nodes_info[0]["iperf_ip"])
         logger.info(f"Running the command: {command2}")