XA Recovery can not connect to any hornetq server on recovery

Issue

After an accidental clustering of two separate environments, one of the clusters repeats the following WARNs, even after the second cluster is isolated or shut down:

2017-07-31 12:48:40,103 WARN  [Periodic Recovery] [server ] HQ122015: Can not connect to XARecoveryConfig [transportConfiguration = [TransportConfiguration(name=netty, factory=org-hornetq-core-remoting-impl-netty-NettyConnectorFactory) ?port=5745&host=xxx-xx-xxx-xx], discoveryConfiguration = null, username=remoteServer, password=****] on auto-generated resource recovery: HornetQException[errorType=NOT_CONNECTED message=HQ119007: Cannot connect to server(s). Tried with all available servers.]

2017-07-31 12:49:10,244 WARN  [Periodic Recovery] [server ] HQ122008: XA Recovery can not connect to any hornetq server on recovery [XARecoveryConfig [transportConfiguration = [TransportConfiguration(name=netty, factory=org-hornetq-core-remoting-impl-netty-NettyConnectorFactory) ?port=5745&host=xxx-xx-xxx-xx], discoveryConfiguration = null, username=remoteServer, password=****]]