The ovsdb:1 is being written twice by two different threads. Looks like the ownership callback is being called twice. The exception below comes out as well as further datastore exceptions. This also happens with the hwvtepsb also since it's code is structured the same.

2016-08-02 09:46:18,470 | WARN | lt-dispatcher-14 | SimpleShardDataTreeCohort | 201 - org.opendaylight.controller.sal-distributed-datastore - 1.4.0.SNAPSHOT | Store Tx TransactionIdentifier{history=LocalHistoryIdentifier{client=ClientIdentifier

{frontend=member-1-frontend-datastore-operational, generation=0}

, history=0, cookie=0}, transaction=5}: Conflicting modification for path /(urn:TBD:params:xml:ns:yang:network-topology?revision=2013-10-21)network-topology/topology/topology[

{(urn:TBD:params:xml:ns:yang:network-topology?revision=2013-10-21)topology-id=ovsdb:1}

].