Merge pull request #4920 from natali-rs1985/T7098

T7098: Fix VPP MTU misconfiguration

2 files changed, 30 insertions, 1 deletions

diff --git a/smoketest/scripts/cli/test_vpp.py b/smoketest/scripts/cli/test_vpp.py
index 9f67b79c8..1886ac615 100755
--- a/smoketest/scripts/cli/test_vpp.py
+++ b/smoketest/scripts/cli/test_vpp.py
@@ -118,6 +118,7 @@ class TestVPP(VyOSUnitTestSHIM.TestCase):
     def test_01_vpp_basic(self):
         main_core = '0'
         poll_sleep = '0'
+        mtu = '2500'
 
         # Main core must be verified
         # expect raise ConfigError
@@ -161,6 +162,19 @@ class TestVPP(VyOSUnitTestSHIM.TestCase):
         required_str = 'lcp route-no-paths off'
         self.assertIn(required_str, out)
 
+        # set interface MTU
+        self.cli_set(['interfaces', 'ethernet', interface, 'mtu', mtu])
+        self.cli_commit()
+
+        # check MTU for the LCP interface pair
+        _, out = rc_cmd('sudo vppctl show interface')
+        normalized_out = re.sub(r'\s+', ' ', out)
+        self.assertIn(f'tap4096 2 up {mtu}/0/0/0', normalized_out)
+
+        # delete mtu settings
+        self.cli_delete(['interfaces', 'ethernet', interface, 'mtu'])
+        self.cli_commit()
+
     def test_02_vpp_vxlan(self):
         vni = '23'
         interface_vxlan = f'vxlan{vni}'
diff --git a/src/conf_mode/interfaces_ethernet.py b/src/conf_mode/interfaces_ethernet.py
index a85ccf815..599421c72 100755
--- a/src/conf_mode/interfaces_ethernet.py
+++ b/src/conf_mode/interfaces_ethernet.py
@@ -46,6 +46,7 @@ from vyos.utils.dict import dict_to_paths_values
 from vyos.utils.dict import dict_set
 from vyos.utils.dict import dict_delete
 from vyos.utils.process import is_systemd_service_running
+from vyos.vpp.control_vpp import VPPControl
 from vyos import ConfigError
 from vyos import airbag
 airbag.enable()
@@ -437,13 +438,27 @@ def generate(ethernet):
 def apply(ethernet):
     if 'frr_dict' in ethernet and not is_systemd_service_running('vyos-configd.service'):
         FRRender().apply()
-    e = EthernetIf(ethernet['ifname'])
+    ifname = ethernet['ifname']
+    e = EthernetIf(ifname)
     if 'deleted' in ethernet:
         e.remove()
     else:
         e.update(ethernet)
     if 'static_arp' in ethernet:
         call_dependents()
+
+    # If the interface is managed by the VPP DPDK driver, synchronize runtime
+    # parameters between Linux and the corresponding VPP LCP interface
+    if dict_search(f'vpp.settings.interface.{ifname}.driver', ethernet) == 'dpdk':
+        vpp_api = VPPControl()
+        # Find LCP pair
+        lcp_pair = vpp_api.lcp_pair_find(vpp_name_hw=ifname)
+        lcp_name = lcp_pair.get('vpp_name_kernel')
+        # Sync MTU to VPP LCP pair interface
+        if lcp_name:
+            mtu = e.get_mtu()
+            vpp_api.set_iface_mtu(lcp_name, mtu)
+
     return None
 
 if __name__ == '__main__':