I had an interesting case of ORA-600 , , ,  few days back, which i am going to share in this post🙂
As part of Oracle streams setup , a downstream capture database was created by me manually. What is Downstream Capture Database ???With Oracle 10g,it is possible to configure the capture process on a database other than the source database. The database where the capture process is configured is called the “Downstream Database” and the capture process is referred to as “Downstream Capture”.
The source database was a 2-node RAC database, and capture database a single instance database.Little background about the capture part,is the archive log files generated at the source database would come to capture database where it would get logmined by the logminer process and LCRs will be created.For enabling the real time mining standby redo log files are required in the capture database.
After creating the standby redo log files on the capture database and enabling real time mining using DBMS_CAPTURE_ADM ,alert log was full with ORA-600.ORA-600  error was continuously reported by the archiver process on the Downstream database.The moment these standby redo log files were dropped, no more ORA-600.Hmmmm, sounds interesting, isn’t it!!!!!!
The reason being “When i manually created the Downstream database, i had set the MAXINSTANCES to 1 “.As per metalink
The Downstream’s database controlfile has been created with an incorrect MAXINSTANCES value. The MAXINSTANCES value needs to be equal to the maximum number of instances (redo threads) which are available on any source database.
Recreated the controlfile with MAXINTANCES 2 and no more ORA-600.
I think it was good that i had created it with value 1, i learned something new🙂