I am running ODL in 3 node cluster with 50 switches linear topology out of which most of switches master is member-1, when I killed this controller I got exception similar to mentioned in this URL https://www.mail-archive.com/openflowplugin-dev@lists.opendaylight.org/msg01287.html# on controller which is trying to take mastership of switches. I also verified in opendaylight-inventory:nodes and network-topology datastores and the switches for which I am getting these exceptions are not present there. I am using carbon SR1 distribution, OVS version 2.5.0 with mininet.

I also checked in ovs-vsctl show and switches are shown connected to the controllers. The exceptions that i got are

2017-09-12 15:06:13,224 | ERROR | CommitFutures-5 | TransactionChainManager | 220 - org.opendaylight.openflowplugin.impl - 0.4.1.Carbon | Transaction commit failed.
TransactionCommitFailedException{message=Data did not pass validation., errorList=[RpcError [message=Data did not pass validation., severity=ERROR, errorType=APPLICATION, tag=operation-failed, applicationTag=null, info=null, cause=org.opendaylight.yangtools.yang.data.api.schema.tree.ModifiedNodeDoesNotExistException: Node /(urn:opendaylight:inventory?revision=2013-08-19)nodes/node/node[

{(urn:opendaylight:inventory?revision=2013-08-19)id=openflow:42}

] does not exist. Cannot apply modification to its children.]]}