While opening the database , if you are getting below ORA-0600 error

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

metalink – 1296264.1

Problem:

SQL>startup
ORA-32004: obsolete or deprecated parameter(s) specified for RDBMS instance
ORACLE instance started.

Total System Global Area 8754618368 bytes
Fixed Size                  4646288 bytes
Variable Size            4160756336 bytes
Database Buffers         4429185024 bytes
Redo Buffers              160030720 bytes
Database mounted.
ORA-00600: internal error code, arguments: [kcratr_nab_less_than_odr]

Solution:

1. start the database in mount stage:

SQL>Startup mount ;
ORA-32004: obsolete or deprecated parameter(s) specified for RDBMS instance
ORACLE instance started.
Total System Global Area 8754618368 bytes
Fixed Size                  4646288 bytes
Variable Size            4160756336 bytes
Database Buffers         4429185024 bytes
Redo Buffers              160030720 bytes
Database mounted.
 

2. Get controlfile and redo file location:

SQL[SYS@BBCRMST1]SQL>>]Show parameter control_files

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
control_files string /u03/oracle/oradata/BBCRMST1/control01.ctl, /u03/oracle/orad
ata/BBCRMST1/control02.ctl

SQL[SYS@BBCRMST1]SQL>>] select a.member, a.group#, b.status from v$logfile a ,v$log b where a.group#=b.group# and b.status='CURRENT';

MEMBER GROUP# STATUS
------------------------------------------------------------------- ---------- ----------------
/u03/oracle/oradata/BBCRMST1/redo06.log 6 CURRENT

3. shutdown the database and take physical backup of controlfile

shutdown abort

cp /u03/oracle/oradata/BBCRMST1/control01.ctl /u03/oracle/oradata/BBCRMST1/control01.ctl_bkup
cp /u03/oracle/oradata/BBCRMST1/control02.ctl /u03/oracle/oradata/BBCRMST1/control02.ctl_bkup

4. startup mount

Startup mount ;

5. Recover the database by applying current logfile: 

recover database using backup controlfile until cancel ;
/u03/oracle/oradata/BBCRMST1/redo06.log
 
SQL> Alter database open resetlogs ;