Solution: ORA-00600: internal error code, arguments: [kcratr1_lastbwr]

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Solution :# 

ORA-00600: internal error code, arguments: [kcratr1_lastbwr]

SQL*Plus: Release 10.2.0.3.0 - Production on Tue Jul 22 10:21:46 2008
Copyright (c) 1982, 2006, Oracle. All Rights Reserved.
Connected to an idle instance.
SQL> startup;
ORACLE instance started.
Total System Global Area 524288000 bytes
Fixed Size 2129656 bytes
Variable Size 161317128 bytes
Database Buffers 356515840 bytes
Redo Buffers 4325376 bytes
Database mounted.
ORA-00600: internal error code, arguments: [kcratr1_lastbwr], [], [], [], [],
[], [], []

SQL> shutdown immediate;
ORA-01109: database not open
Database dismounted.
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started.
Total System Global Area 524288000 bytes
Fixed Size 2129656 bytes
Variable Size 161317128 bytes
Database Buffers 356515840 bytes
Redo Buffers 4325376 bytes
Database mounted.
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-00600: internal error code, arguments: [kcratr1_lastbwr], [], [], [], [],
[], [], []

SQL> recover database;
Media recovery complete.
SQL> alter database open;
Database altered.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup;
ORACLE instance started.
Total System Global Area 524288000 bytes
Fixed Size 2129656 bytes
Variable Size 161317128 bytes
Database Buffers 356515840 bytes
Redo Buffers 4325376 bytes
Database mounted.
Database opened.
SQL> exit;

Solution: Alter database open fails with ORA-00600 kcratr_nab_less_than_odr [ID 1296264.1]

Solution : # 
------------
SQL>Startup mount ;

SQL>Show parameter control_files

Query 1
------------
sql>select a.member,a.group#,b.status from v$logfile a ,v$log b where a.group#=b.group# and b.status='CURRENT'

Note down the name of the redo log

SQL>Shutdown abort ;
Take a OS Level backup of the controlfile (This is to ensure we have a backup of current state of controlfile)
SQL>Startup mount ;
SQL>recover database using backup controlfile until cancel ;
Enter location of redo log shown as current in Query 1 when prompted for recovery
Hit Enter
SQL>Alter database open resetlogs ;

Solution :#-----------Recreate the controlfile using the Controlfile recreation script

With database in mount stage
rman target /
rman> spool log to '/tmp/rman.log';
Rman> list backup ;
Rman > exit
Keep this log handy
Go to sqlplus
SQL> Show parameter control_files
Keep this location handy.
SQL>oradebug setmypid
SQL>Alter session set tracefile_identifier='controlfilerecreate' ;
SQL>Alter database backup controlfile to trace ;
SQL>Oradebug tracefile_name ;       --> This command will give the path and name of the trace file
Go to this location ,Open this trace file and select the controlfile recreation script with NO Resetlogs option
SQL>Shutdown immediate;
Rename the existing controlfile to <originalname>_old ---> This is Important as we need to have a backup of existing controlfile since we plan to recreate it
SQL>Startup nomount
Now run the Controlfile recreation script with NO Resetlogs mode
SQL>Alter database open ;
For database version 10g and above
Once database is opened you can recatalog the rman backup information present in the list /tmp/rman.log using
Rman> Catalog start with '<location of backupiece>' ;

Solution: ORA-600 [kcratr_nab_less_than_odr] during Instance Recovery after Database Crash [ID 1299564.1]

There are two possible Solutions:
1. If you could restore your Storage Environment and the Online RedoLogs from the Time of the crash you can try a manual Recovery followed by a RESETLOGS:
SQL> startup mount;
SQL> recover database until cancel using backup controlfile;
-> manually provide Online RedoLog containing the last (current) Sequence when asked, eg.
ORA-00279: change 100000 generated at xx/xx/xxxx xx:xx:xx needed for thread 1
ORA-00289: suggestion :

/flash_recovery/archivelog/xxxx_xx_xx/o1_mf_1_100_%u_.arc
ORA-00280: change 100000 for thread 1 is in sequence #100

Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
/ora/oradata/dbtest/redo04_1.rdo
Log applied.
Media recovery complete.

SQL> alter database open resetlogs;

2. If  step1. fails or you don't have the full Set of Files you have to restore and recover the Database from a recent Backup