ifconfig: T3806: "ipv6 address no_default_link_local" required for MTU < 1280

This commit also extends the smoketest to verify that the exception for this
error is raised.

3 files changed, 28 insertions, 21 deletions

diff --git a/python/vyos/configverify.py b/python/vyos/configverify.py
index 7f49aa9af..760255d0e 100644
--- a/python/vyos/configverify.py
+++ b/python/vyos/configverify.py
@@ -67,22 +67,22 @@ def verify_mtu_ipv6(config):
         min_mtu = 1280
         if int(config['mtu']) < min_mtu:
             interface = config['ifname']
-            error_msg = f'IPv6 address will be configured on interface "{interface}" ' \
-                        f'thus the minimum MTU requirement is {min_mtu}!'
+            error_msg = f'IPv6 address will be configured on interface "{interface}",\n' \
+                        f'the required minimum MTU is {min_mtu}!'
 
-            for address in (dict_search('address', config) or []):
-                if address in ['dhcpv6'] or is_ipv6(address):
-                    raise ConfigError(error_msg)
+            if 'address' in config:
+                for address in config['address']:
+                    if address in ['dhcpv6'] or is_ipv6(address):
+                        raise ConfigError(error_msg)
 
-            tmp = dict_search('ipv6.address', config)
-            if tmp and 'no_default_link_local' not in tmp:
-                raise ConfigError('link-local ' + error_msg)
+            tmp = dict_search('ipv6.address.no_default_link_local', config)
+            if tmp == None: raise ConfigError('link-local ' + error_msg)
 
-            if tmp and 'autoconf' in tmp:
-                raise ConfigError(error_msg)
+            tmp = dict_search('ipv6.address.autoconf', config)
+            if tmp != None: raise ConfigError(error_msg)
 
-            if tmp and 'eui64' in tmp:
-                raise ConfigError(error_msg)
+            tmp = dict_search('ipv6.address.eui64', config)
+            if tmp != None: raise ConfigError(error_msg)
 
 def verify_vrf(config):
     """
diff --git a/smoketest/scripts/cli/base_interfaces_test.py b/smoketest/scripts/cli/base_interfaces_test.py
index edb604dbf..6a5b9c4ee 100644
--- a/smoketest/scripts/cli/base_interfaces_test.py
+++ b/smoketest/scripts/cli/base_interfaces_test.py
@@ -246,11 +246,19 @@ class BasicInterfaceTest:
             for intf in self._interfaces:
                 base = self._base_path + [intf]
                 self.cli_set(base + ['mtu', self._mtu])
-                self.cli_set(base + ['ipv6', 'address', 'no-default-link-local'])
 
                 for option in self._options.get(intf, []):
                     self.cli_set(base + option.split())
 
+            # check validate() - can not set low MTU if 'no-default-link-local'
+            # is not set on CLI
+            with self.assertRaises(ConfigSessionError):
+                self.cli_commit()
+
+            for intf in self._interfaces:
+                base = self._base_path + [intf]
+                self.cli_set(base + ['ipv6', 'address', 'no-default-link-local'])
+
             # commit interface changes
             self.cli_commit()
 
diff --git a/src/conf_mode/interfaces-ethernet.py b/src/conf_mode/interfaces-ethernet.py
index 81ed36bf2..2a094af52 100755
--- a/src/conf_mode/interfaces-ethernet.py
+++ b/src/conf_mode/interfaces-ethernet.py
@@ -72,6 +72,13 @@ def verify(ethernet):
 
     ifname = ethernet['ifname']
     verify_interface_exists(ifname)
+    verify_mtu(ethernet)
+    verify_mtu_ipv6(ethernet)
+    verify_dhcpv6(ethernet)
+    verify_address(ethernet)
+    verify_vrf(ethernet)
+    verify_eapol(ethernet)
+    verify_mirror(ethernet)
 
     ethtool = Ethtool(ifname)
     # No need to check speed and duplex keys as both have default values.
@@ -111,14 +118,6 @@ def verify(ethernet):
             raise ConfigError(f'Driver only supports a maximum TX ring-buffer '\
                               f'size of "{max_tx}" bytes!')
 
-    verify_mtu(ethernet)
-    verify_mtu_ipv6(ethernet)
-    verify_dhcpv6(ethernet)
-    verify_address(ethernet)
-    verify_vrf(ethernet)
-    verify_eapol(ethernet)
-    verify_mirror(ethernet)
-
     # verify offloading capabilities
     if dict_search('offload.rps', ethernet) != None:
         if not os.path.exists(f'/sys/class/net/{ifname}/queues/rx-0/rps_cpus'):