Snippet from exception (full in attached log file):

2015-07-02 06:32:46,840 | ERROR | tp1481334572-303 | ContainerResponse | 245 - com.sun.jersey.jersey-server - 1.17.0 | The RuntimeException could not be mapped to a response, re-throwing to the HTTP container
java.lang.NullPointerException: Tree must not be null
at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:226)[64:com.google.guava:18.0.0]
at org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodes.findNode(NormalizedNodes.java:77)[99:org.opendaylight.yangtools.yang-data-api:0.7.0.Lithium]
at org.opendaylight.controller.md.sal.dom.broker.impl.RoutedDOMRpcRoutingTableEntry.invokeRpc(RoutedDOMRpcRoutingTableEntry.java:47)
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMRpcRoutingTable.invokeRpc(DOMRpcRoutingTable.java:186)
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMRpcRouter.invokeRpc(DOMRpcRouter.java:124)
at org.opendaylight.controller.sal.restconf.impl.BrokerFacade.invokeRpc(BrokerFacade.java:172)[242:org.opendaylight.controller.sal-rest-connector:1.2.0.Lithium]
at org.opendaylight.controller.sal.restconf.impl.RestconfImpl.invokeRpc(RestconfImpl.java:451)[242:org.opendaylight.controller.sal-rest-connector:1.2.0.Lithium]
at org.opendaylight.controller.sal.restconf.impl.StatisticsRestconfServiceWrapper.invokeRpc(StatisticsRestconfServiceWrapper.java:81)[242:org.opendaylight.controller.sal-rest-connector:1.2.0.Lithium]
at org.opendaylight.controller.sal.rest.impl.RestconfCompositeWrapper.invokeRpc(RestconfCompositeWrapper.java:53)[242:org.opendaylight.controller.sal-rest-connector:1.2.0.Lithium]
at sun.reflect.GeneratedMethodAccessor92.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)[:1.7.0_75]
at java.lang.reflect.Method.invoke(Method.java:606)[:1.7.0_75]

Please find attached the log with trace enabled. Out of 100 tunnels, 92 were provisioned and 8 failed with errors. (with Helium SR-3, all 100 gets provisioned).