The following is the ORA-16599 error message, you can learn the cause and solution of the Oracle database error.

ORA-16599 The Data Guard broker has detected a stale configuration

Cause: The Data Guard broker has detected a stale configuration during initialization on this site.

Solution: The broker will automatically resolve this situation once the primary site completes its initialization.


How to Diagnose
1. Please check the alert.log if there are other errors at the time the ORA-12805 happened.

2. Errors like ORA-600/ORA-7445 can cause a crash of a slave process and so a parallel query fails with a ORA-12805.

3. Also check if there are trace files created at the time the ORA-12805 happened.

In case you have a RAC system, please check also the alert.log and the trace folder on the other nodes. In a RAC system a parallel query can spawn slave processes on other nodes.
On RAC system look for entries like “IPC Send timeout detected…” in the alert.logs at the time the ORA-12805 happened. If you see entries like this, then investigate the interconnect if there are network error. It is also possible that there are problems in the software of the communication layer.
If the ORA-12805 is reproducible, then the trace information coming out of the following px_trace can be helpful for Oracle Support:

alter session set MAX_DUMP_FILE_SIZE= unlimited;
alter session set TRACEFILE_IDENTIFIER = ‘ORA12805’
alter session set “_px_trace”=medium, execution, medium, messaging, time;
— Reproduce the error here in the session
alter session set “_px_trace”=none ;

This tracing does not help if you have a ORA-12805 caused by Join ACK time out.
In such case, you will see few lines something like mentioned below.
Time-out waiting for slave Join Ack: passes:2 waits:2 csrret:3
sleeptime:200 timeouts:0 ghostposts 0
start:722026 end:722033 diff:7 ksl:728143 avg_ksl:364071

A slave process does not respond to a Join ACK message. Here the alter session tracing does not help, because the slave does not start to trace.
It can also help to get an errorstack for the ORA-12805. Set in the init.ora

event=”12805 trace name ERRORSTACK level 3”
alter system set events = ‘12805 trace name ERRORSTACK level 3’;