ODL Version : distribution-karaf-0.5.2-Boron-SR2

Openstack Version : mitaka

Setup Details : 3 ODL Nodes + 1 Control Node + 2 Compute Nodes

Steps to Reproduce:
1. Start karaf and install odl-ovsdb-openstack and jolokia bundle
2. Check cluster is formed. And check network topology is initiated
3. Check the entity owner list and confirm the "OWNER" node (say member-2).
4. Logout the "OWNER" node and verify the entity owner previous owner will be removed and new owner node will be assigned.
5. In the remaining two nodes (say member-1 and member-3) "CandidateAlreadyRegisteredException" is been observed in the karaf logs.

Observation:

When "Owner" node goes down, one of the remaining two nodes act as "MASTER" and other as "SLAVE". Only at this time "CandidateAlreadyRegisteredException" is been observed. The exception is not observed when ODLs are not connect with OVS. Only when it is connected OVS, the exception is reproduced.

karaf.log:1755:org.opendaylight.controller.md.sal.common.api.clustering.CandidateAlreadyRegisteredException: Candidate has already been registered for Entity{type='ovsdb', id=/(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}

]/node/node[

{(urn:TBD:params:xml:ns:yang:network-topology?revision=2013-10-21)node-id=ovsdb://uuid/24e237d2-70d7-4e10-9d50-2dd4a680f70a}

]}
karaf.log:1768:org.opendaylight.controller.md.sal.common.api.clustering.CandidateAlreadyRegisteredException: Candidate has already been registered for Entity{type='ovsdb', id=/(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}

]/node/node[

{(urn:TBD:params:xml:ns:yang:network-topology?revision=2013-10-21)node-id=ovsdb://uuid/edc5f467-d8e8-469a-b451-83e832f43bb9}

]}
karaf.log:1781:org.opendaylight.controller.md.sal.common.api.clustering.CandidateAlreadyRegisteredException: Candidate has already been registered for Entity{type='ovsdb', id=/(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}

]/node/node[

{(urn:TBD:params:xml:ns:yang:network-topology?revision=2013-10-21)node-id=ovsdb://uuid/fa6ea16b-52dd-4366-883d-2d2ed3e26834}

]}

Note:
24e237d2-70d7-4e10-9d50-2dd4a680f70a – Control Node UUID
fa6ea16b-52dd-4366-883d-2d2ed3e26834 – Compute Node1 UUID
edc5f467-d8e8-469a-b451-83e832f43bb9 – Compute Node2 UUID

The above exception will not affect any functionality.

Please find the attached files for karaf logs and entity owner details.