Restore execution of FloatingIpWithMtuWritableTest

Test floating IP with a network with a custom MTU
size.

Change-Id: I47ff6e0dc5eee366951ac46b52c471bbbb58a555

tobiko/openstack/neutron/config.py

@@ -32,4 +32,14 @@ def register_tobiko_options(conf):
                          help="The CIDR block to allocate IPv6 subnets from"),
               cfg.IntOpt('ipv6_prefixlen',
                          default=64,
-                         help="The mask bits for IPv6 subnets")])
+                         help="The mask bits for IPv6 subnets"),
+              cfg.IntOpt('custom_mtu_size',
+                         default=1400,
+                         help=("Customized maximum transfer unit size\n"
+                               "Notes:\n"
+                               " - MTU values as small as 1000 has been seen "
+                               "breaking networking binding due to an "
+                               "unknown cause.\n"
+                               " - Too big MTU values (like greater than 1400)"
+                               " may be refused during network creation")),
+              ])

tobiko/openstack/stacks/_neutron.py

@@ -16,6 +16,7 @@
 from __future__ import absolute_import
 
 import netaddr
+from oslo_log import log
 
 import tobiko
 from tobiko import config
@@ -28,6 +29,7 @@ from tobiko.shell import ssh
 
 
 CONF = config.CONF
+LOG = log.getLogger(__name__)
 
 
 @neutron.skip_if_missing_networking_extensions('port-security')
@@ -68,16 +70,20 @@ class NetworkStackFixture(heat.HeatStackFixture):
     def value_specs(self):
         return {}
 
-    #: Floating IP network where the Neutron floating IPs are created
-    gateway_network = CONF.tobiko.neutron.floating_network
+    @property
+    def gateway_network(self):
+        """Floating IP network where the Neutron floating IPs are created"""
+        return CONF.tobiko.neutron.floating_network
 
     @property
     def has_gateway(self):
         """Whenever to setup gateway router"""
         return bool(self.gateway_network)
 
-    # Whenever cat obtain network MTU value
-    has_net_mtu = neutron.has_networking_extensions('net-mtu')
+    @property
+    def has_net_mtu(self):
+        """Whenever can obtain network MTU value"""
+        return neutron.has_networking_extensions('net-mtu')
 
     @property
     def network_details(self):
@@ -129,17 +135,15 @@ class NetworkStackFixture(heat.HeatStackFixture):
 @neutron.skip_if_missing_networking_extensions('net-mtu-writable')
 class NetworkWithNetMtuWriteStackFixture(NetworkStackFixture):
 
-    # Whenever cat obtain network MTU value
-    has_net_mtu = True
-
-    #: Value for maximum transfer unit on the internal network
-    mtu = 1000
+    @property
+    def custom_mtu_size(self):
+        return CONF.tobiko.neutron.custom_mtu_size
 
     @property
     def value_specs(self):
-        return dict(
-            super(NetworkWithNetMtuWriteStackFixture, self).value_specs,
-            mtu=int(self.mtu))
+        value_specs = super(
+            NetworkWithNetMtuWriteStackFixture, self).value_specs
+        return dict(value_specs, mtu=self.custom_mtu_size)
 
 
 @neutron.skip_if_missing_networking_extensions('security-group')

tobiko/tests/scenario/neutron/test_floating_ip.py

@@ -108,18 +108,6 @@ class FloatingIPTest(base.TobikoTest):
                   count=5,
                   check=False).assert_not_replied()
 
-    @neutron.skip_if_missing_networking_extensions('net-mtu-writable')
-    def test_mtu_net_attribute(self):
-        """Test 'mtu' network attribute"""
-        if self.expected_net_mtu:
-            self.assertEqual(self.expected_net_mtu,
-                             self.observed_net_mtu)
-
-    @property
-    def expected_net_mtu(self):
-        """Expected MTU value for internal network"""
-        return self.stack.network_stack.mtu
-
     @property
     def observed_net_mtu(self):
         """Actual MTU value for internal network"""
@@ -220,13 +208,17 @@ class FloatingIPWithNetMtuWritableFixture(stacks.FloatingIpServerStackFixture):
 
 
 @neutron.skip_if_missing_networking_extensions('net-mtu-writable')
-class FlatingIpWithMtuWritableTest(FloatingIPTest):
+class FloatingIpWithMtuWritableTest(FloatingIPTest):
     """Tests connectivity via floating IP with a custom MTU value"""
 
     #: Resources stack with floating IP and Nova server
     stack = tobiko.required_setup_fixture(FloatingIPWithNetMtuWritableFixture)
 
-    @classmethod
-    def setUpClass(cls):
-        super(FlatingIpWithMtuWritableTest, cls).setUpClass()
-        tobiko.skip('Disable this test to see if it fixes the problem')
+    def test_net_mtu_write(self):
+        """Test 'mtu' network attribute"""
+        self.assertEqual(self.expected_net_mtu, self.observed_net_mtu)
+
+    @property
+    def expected_net_mtu(self):
+        """Expected MTU value for internal network"""
+        return self.stack.network_stack.custom_mtu_size