Error in sending a reply message to a replica database
The transfer of a reply message from the master database to a replica database can fail because of a networking error. In this case, the message remains in the master database.
You can use the following query in the replica database to list messages that were sent to the master database but have not received replies:
SELECT MSG_NAME FROM SYS_SYNC_REPLICA_MSGINFO WHERE STATE = 23
You can request the message again from the master database by using the MESSAGE GET REPLY statement, see MESSAGE GET REPLY.
For information about the possible values of the STATE column of the SYS_SYNC_REPLICA_MSGINFO table, see SYS_SYNC_REPLICA_MSGINFO.