diff --git a/ansible/roles/test/files/ptftests/fib_test.py b/ansible/roles/test/files/ptftests/fib_test.py
index 7d4775a5f92..8f085c945f7 100644
--- a/ansible/roles/test/files/ptftests/fib_test.py
+++ b/ansible/roles/test/files/ptftests/fib_test.py
@@ -87,6 +87,7 @@ def setUp(self):
         self.dataplane = ptf.dataplane_instance
         self.fib = fib.Fib(self.test_params['fib_info'])
         self.router_mac = self.test_params['router_mac']
+        self.pktlen = self.test_params['testbed_mtu']
 
         self.test_ipv4 = self.test_params.get('ipv4', True)
         self.test_ipv6 = self.test_params.get('ipv6', True)
@@ -173,6 +174,7 @@ def check_ipv4_route(self, src_port, dst_ip_addr, dst_port_list):
         src_mac = self.dataplane.get_mac(0, 0)
 
         pkt = simple_tcp_packet(
+                            pktlen=self.pktlen,
                             eth_dst=self.router_mac,
                             eth_src=src_mac,
                             ip_src=ip_src,
@@ -181,6 +183,7 @@ def check_ipv4_route(self, src_port, dst_ip_addr, dst_port_list):
                             tcp_dport=dport,
                             ip_ttl=64)
         exp_pkt = simple_tcp_packet(
+                            self.pktlen,
                             eth_src=self.router_mac,
                             ip_src=ip_src,
                             ip_dst=ip_dst,
@@ -211,6 +214,7 @@ def check_ipv6_route(self, src_port, dst_ip_addr, dst_port_list):
         src_mac = self.dataplane.get_mac(0, 0)
 
         pkt = simple_tcpv6_packet(
+                                pktlen=self.pktlen,
                                 eth_dst=self.router_mac,
                                 eth_src=src_mac,
                                 ipv6_dst=ip_dst,
@@ -219,6 +223,7 @@ def check_ipv6_route(self, src_port, dst_ip_addr, dst_port_list):
                                 tcp_dport=dport,
                                 ipv6_hlim=64)
         exp_pkt = simple_tcpv6_packet(
+                                pktlen=self.pktlen,
                                 eth_src=self.router_mac,
                                 ipv6_dst=ip_dst,
                                 ipv6_src=ip_src,
diff --git a/ansible/roles/test/tasks/simple-fib.yml b/ansible/roles/test/tasks/simple-fib.yml
index e21b16a71fc..889538da3c3 100644
--- a/ansible/roles/test/tasks/simple-fib.yml
+++ b/ansible/roles/test/tasks/simple-fib.yml
@@ -6,6 +6,9 @@
 
 - debug : msg="Start FIB Test"
 
+- set_fact: mtu=9114
+  when: mtu is not defined
+
 - name: "Start PTF runner"
   include: ptf_runner.yml
   vars:
@@ -20,4 +23,5 @@
       - fib_info='/root/fib_info.txt'
       - ipv4={{ipv4}}
       - ipv6={{ipv6}}
-    ptf_extra_options: "--relax --debug info --log-file /tmp/fib_test.FibTest.ipv4.{{ipv4}}.ipv6.{{ipv6}}.{{lookup('pipe','date +%Y-%m-%d-%H:%M:%S')}}.log "
+      - testbed_mtu={{mtu}}
+    ptf_extra_options: "--relax --debug info --log-file /tmp/fib_test.FibTest.ipv4.{{ipv4}}.ipv6.{{ipv6}}.{{lookup('pipe','date +%Y-%m-%d-%H:%M:%S')}}.log --socket-recv-size 16384"