CLOUDSTACK-5967: GRE tunnel creation is failing

after network orchestrator refactor, only network elements providingg
services as defined by network offering, are invloved network design and
imlement phase. So OVS network element need to be enables as
'Connectivity' service provider to make GRE tunnels work. This fix
introduced 'Ovs' provider as Connectivity service provider.

Conflicts:
	server/src/com/cloud/network/NetworkServiceImpl.java

Author: murali-reddy

api/src/com/cloud/network/Network.java

@@ -127,6 +127,7 @@ public static class Provider {
         public static final Provider NiciraNvp = new Provider("NiciraNvp", false);
         public static final Provider InternalLbVm = new Provider("InternalLbVm", false);
         public static final Provider CiscoVnmc = new Provider("CiscoVnmc", true);
+        public static final Provider Ovs = new Provider("Ovs", false);
 
         private String name;
         private boolean isExternal;

plugins/hypervisors/xen/src/com/cloud/hypervisor/xen/resource/CitrixResourceBase.java

@@ -895,7 +895,12 @@ private void enableXenServerNetwork(Connection conn, Network nw,
             dom0vif = VIF.create(conn, vifr);
         }
         // At this stage we surely have a VIF
-        dom0vif.plug(conn);
+        try {
+            dom0vif.plug(conn);
+        } catch (Exception e) {
+            // though wierd exception is thrown, VIF actually gets plugged-in to dom0, so just ignore exception
+            s_logger.info("Ignoring the benign error thrown while plugging VIF to dom0");
+        }
         dom0vif.unplug(conn);
         synchronized(_tmpDom0Vif) {
             _tmpDom0Vif.add(dom0vif);

plugins/network-elements/ovs/src/com/cloud/network/element/OvsElement.java

@@ -16,6 +16,7 @@
 // under the License.
 package com.cloud.network.element;
 
+import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
 
@@ -53,12 +54,14 @@ public boolean destroy(Network network, ReservationContext context)
 
     @Override
     public Map<Service, Map<Capability, String>> getCapabilities() {
-        return null;
+        Map<Service, Map<Capability, String>> capabilities = new HashMap<Service, Map<Capability, String>>();
+        capabilities.put(Service.Connectivity, null);
+        return capabilities;
     }
 
     @Override
     public Provider getProvider() {
-        return null;
+        return Network.Provider.Ovs;
     }
 
     @Override

server/src/com/cloud/network/NetworkServiceImpl.java

@@ -2472,8 +2472,14 @@ public PhysicalNetwork createPhysicalNetwork(Long zoneId, String vnetRange, Stri
             //Add Internal Load Balancer element as a default network service provider
             addDefaultInternalLbProviderToPhysicalNetwork(pNetwork.getId());
 
+            // Add OVS provider as default network service provider
+            if (pNetwork.getIsolationMethods().contains("GRE")) {
+                addDefaultOvsToPhysicalNetwork(pNetwork.getId());
+            }
+
             txn.commit();
             return pNetwork;
+
         } catch (Exception ex) {
             s_logger.warn("Exception: ", ex);
             throw new CloudRuntimeException("Fail to create a physical network");
@@ -3740,6 +3746,11 @@ private PhysicalNetworkServiceProvider addDefaultBaremetalProvidersToPhysicalNet
         return null;
     }
 
+    private PhysicalNetworkServiceProvider addDefaultOvsToPhysicalNetwork(long physicalNetworkId) {
+        PhysicalNetworkServiceProvider nsp = addProviderToPhysicalNetwork(physicalNetworkId, Network.Provider.Ovs.getName(), null, null);
+        return nsp;
+    }
+
     protected boolean isNetworkSystem(Network network) {
         NetworkOffering no = _networkOfferingDao.findByIdIncludingRemoved(network.getNetworkOfferingId());
         if (no.isSystemOnly()) {