Determine shared ip from table instead of flag

Partially-implements blueprint better-support-for-multiple-networks

Change-Id: Id7c6620704fef504d23cb42c5218251fa9e2dba7

nova/network/linux_net.py

@@ -1427,7 +1427,7 @@ class LinuxBridgeInterfaceDriver(LinuxNetInterfaceDriver):
                           iface,
                           network, gateway)
 
-        if CONF.share_dhcp_address:
+        if network['share_address'] or CONF.share_dhcp_address:
             isolate_dhcp_address(iface, network['dhcp_server'])
         # NOTE(vish): applying here so we don't get a lock conflict
         iptables_manager.apply()
@@ -1444,7 +1444,7 @@ class LinuxBridgeInterfaceDriver(LinuxNetInterfaceDriver):
             LinuxBridgeInterfaceDriver.remove_bridge(network['bridge'],
                                                      gateway)
 
-        if CONF.share_dhcp_address:
+        if network['share_address'] or CONF.share_dhcp_address:
             remove_isolate_dhcp_address(iface, network['dhcp_server'])
 
         iptables_manager.apply()

nova/network/manager.py

@@ -310,11 +310,15 @@ class NetworkManager(manager.Manager):
     def _import_ipam_lib(self, ipam_lib):
         self.ipam = importutils.import_module(ipam_lib).get_ipam_lib(self)
 
+    @staticmethod
+    def _uses_shared_ip(network):
+        shared = network.get('share_address') or CONF.share_dhcp_address
+        return not network.get('multi_host') or shared
+
     @utils.synchronized('get_dhcp')
     def _get_dhcp_ip(self, context, network_ref, host=None):
         """Get the proper dhcp address to listen on."""
-        # NOTE(vish): this is for compatibility
-        if not network_ref.get('multi_host') or CONF.share_dhcp_address:
+        if self._uses_shared_ip(network_ref):
             return network_ref['gateway']
 
         if not host:
@@ -1985,7 +1989,7 @@ class VlanManager(RPCAllocateFixedIP, floating_ips.FloatingIP, NetworkManager):
                 LOG.debug("Remove unused gateway %s", network['bridge'])
                 self.driver.kill_dhcp(dev)
                 self.l3driver.remove_gateway(network)
-                if not CONF.share_dhcp_address:
+                if not self._uses_shared_ip(network):
                     fip = fixed_ip_obj.FixedIP.get_by_address(
                         context, network.dhcp_server)
                     fip.allocated = False

nova/objects/network.py

@@ -24,9 +24,10 @@ from nova.objects import fields
 network_opts = [
     cfg.BoolOpt('share_dhcp_address',
                 default=False,
-                help='If True in multi_host mode, all compute hosts share '
-                     'the same dhcp address. The same IP address used for '
-                     'DHCP will be added on each nova-network node which '
+                help='DEPRECATED: THIS VALUE SHOULD BE SET WHEN CREATING THE '
+                     'NETWORK. If True in multi_host mode, all compute hosts '
+                     'share the same dhcp address. The same IP address used '
+                     'for DHCP will be added on each nova-network node which '
                      'is only visible to the vms on the same host.'),
     cfg.IntOpt('network_device_mtu',
                help='MTU setting for network interface'),

nova/tests/network/test_linux_net.py

@@ -490,8 +490,8 @@ class LinuxNetworkTestCase(test.NoDBTestCase):
         self.stubs.Set(linux_net.iptables_manager.ipv4['filter'],
                        'add_rule', verify_add_rule)
         driver = linux_net.LinuxBridgeInterfaceDriver()
-        driver.plug({"bridge": "br100", "bridge_interface": "eth0"},
-                    "fakemac")
+        driver.plug({"bridge": "br100", "bridge_interface": "eth0",
+                     "share_address": False}, "fakemac")
 
     def test_linux_ovs_driver_plug_exception(self):
         self.flags(fake_network=False)
@@ -529,6 +529,7 @@ class LinuxNetworkTestCase(test.NoDBTestCase):
         network = {
                 "bridge": "br100",
                 "bridge_interface": "base_interface",
+                "share_address": False,
                 "vlan": "fake"
         }
         self.flags(vlan_interface="")
@@ -559,6 +560,7 @@ class LinuxNetworkTestCase(test.NoDBTestCase):
         network = {
                 "bridge": "br100",
                 "bridge_interface": "base_interface",
+                "share_address": False,
         }
         driver.plug(network, "fakemac")
         self.assertEqual(info['passed_interface'], "base_interface")
@@ -676,6 +678,7 @@ class LinuxNetworkTestCase(test.NoDBTestCase):
         iface = 'eth0'
         dhcp = '192.168.1.1'
         network = {'dhcp_server': dhcp,
+                   'share_address': False,
                    'bridge': 'br100',
                    'bridge_interface': iface}
         driver.plug(network, 'fakemac')
@@ -767,6 +770,7 @@ class LinuxNetworkTestCase(test.NoDBTestCase):
         iface = 'eth0'
         dhcp = '192.168.1.1'
         network = {'dhcp_server': dhcp,
+                   'share_address': False,
                    'bridge': 'br100',
                    'bridge_interface': iface}
         driver.plug(network, 'fakemac')