After sending the below request, adding an already existing OVS instance to the config tree, the error from karaf (below the request) appears. This exception does not happen if the controller is the connection initiator. Moreover this error is repeated whenever a QOS entry or a QUEUE entry is added to the config tree under the OVS node.

It appears that QOS and QUEUEs cannot be configured unless the controller is the connection initiator.

PUT /restconf/config/network-topology:network-topology/topology/ovsdb:1/node/ovsdb%3A%2F%2Fuuid%2F2c7ecb6c-41b1-4e6a-9ef9-6c98f0768400 HTTP/1.1
Host: localhost:8181
Content-Type: application/json
Cache-Control: no-cache
Postman-Token: 332e6e95-850e-be1a-98f4-68eeeb8a40f2

{
"node":

{ "node-id": "ovsdb://uuid/2c7ecb6c-41b1-4e6a-9ef9-6c98f0768400" }

}

2016-06-23 12:07:27,069 | ERROR | on-dispatcher-38 | DataChangeListener | 291 - org.opendaylight.controller.sal-distributed-datastore - 1.3.1.Beryllium-SR1 | Error notifying listener org.opendaylight.ovsdb.southbound.OvsdbDataChangeListener
java.lang.NullPointerException
at org.opendaylight.ovsdb.southbound.OvsdbDataChangeListener.connectionInstancesFromMap(OvsdbDataChangeListener.java:207)[299:org.opendaylight.ovsdb.southbound-impl:1.2.2.Beryllium-SR1]
at org.opendaylight.ovsdb.southbound.OvsdbDataChangeListener.connectionInstancesFromChanges(OvsdbDataChangeListener.java:180)[299:org.opendaylight.ovsdb.southbound-impl:1.2.2.Beryllium-SR1]
at org.opendaylight.ovsdb.southbound.OvsdbDataChangeListener.updateData(OvsdbDataChangeListener.java:95)[299:org.opendaylight.ovsdb.southbound-impl:1.2.2.Beryllium-SR1]
at org.opendaylight.ovsdb.southbound.OvsdbDataChangeListener.onDataChanged(OvsdbDataChangeListener.java:82)[299:org.opendaylight.ovsdb.southbound-impl:1.2.2.Beryllium-SR1]
at org.opendaylight.controller.md.sal.binding.impl.AbstractForwardedDataBroker$TranslatingDataChangeInvoker.onDataChanged(AbstractForwardedDataBroker.java:143)[266:org.opendaylight.controller.sal-binding-broker-impl:1.3.1.Beryllium-SR1]
at org.opendaylight.controller.cluster.datastore.DataChangeListener.dataChanged(DataChangeListener.java:66)[291:org.opendaylight.controller.sal-distributed-datastore:1.3.1.Beryllium-SR1]
at org.opendaylight.controller.cluster.datastore.DataChangeListener.handleReceive(DataChangeListener.java:39)[291:org.opendaylight.controller.sal-distributed-datastore:1.3.1.Beryllium-SR1]
at org.opendaylight.controller.cluster.common.actor.AbstractUntypedActor.onReceive(AbstractUntypedActor.java:34)[287:org.opendaylight.controller.sal-clustering-commons:1.3.1.Beryllium-SR1]
at akka.actor.UntypedActor$$anonfun$receive$1.applyOrElse(UntypedActor.scala:167)[276:com.typesafe.akka.actor:2.3.14]
at akka.actor.Actor$class.aroundReceive(Actor.scala:467)[276:com.typesafe.akka.actor:2.3.14]
at akka.actor.UntypedActor.aroundReceive(UntypedActor.scala:97)[276:com.typesafe.akka.actor:2.3.14]
at akka.actor.ActorCell.receiveMessage(ActorCell.scala:516)[276:com.typesafe.akka.actor:2.3.14]
at akka.actor.ActorCell.invoke(ActorCell.scala:487)[276:com.typesafe.akka.actor:2.3.14]
at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:238)[276:com.typesafe.akka.actor:2.3.14]
at akka.dispatch.Mailbox.run(Mailbox.scala:220)[276:com.typesafe.akka.actor:2.3.14]
at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:397)[276:com.typesafe.akka.actor:2.3.14]
at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)[273:org.scala-lang.scala-library:2.11.7.v20150622-112736-1fbce4612c]
at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)[273:org.scala-lang.scala-library:2.11.7.v20150622-112736-1fbce4612c]
at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)[273:org.scala-lang.scala-library:2.11.7.v20150622-112736-1fbce4612c]
at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)[273:org.scala-lang.scala-library:2.11.7.v20150622-112736-1fbce4612c]