[oracle@rac2 bdump]$ cp alert_orcl2.log alert_orcl2_before_201408111624_bak.log

[oracle@rac2 bdump]$ true > alert_orcl2.log

SQL> alter system switch logfile;
System altered.

SQL> conn test / 123
Connected.
SQL> create directory bdump as '/oracle/u01/app/oracle/admin/db2/bdump';
Directory created.

SQL> create table alert_log(
text varchar2(400)
)organization external
(type oracle_loader
default directory bdump
access parameters
(records delimited by newline
)location('alert_db2.log')
);

SQL> select * from alert_log where rownum < 10;
TEXT
--------------------------------------------------------------------------------
Thu Jun 11 00:51:46 2009
Starting ORACLE instance (normal)
Cannot determine all dependent dynamic libraries for /proc/self/exe
Unable to find dynamic library libocr10.so in search paths
RPATH = /ade/aime1_build2101/oracle/has/lib/:/ade/aime1_build2101/oracle/lib/:/a
de/aime1_build2101/oracle/has/lib/:
LD_LIBRARY_PATH is not set!
The default library directories are /lib and /usr/lib
Unable to find dynamic library libocrb10.so in search paths
Unable to find dynamic library libocrutl10.so in search paths
9 rows selected.

SQL> select * from alert_log where text like 'ORA-%';
TEXT
--------------------------------------------------------------------------------
ORA-00202: control file: '/oracle/u01/app/oracle/product/10.2.0/db2/dbs/cntrldb2
.dbf'
ORA-27037: unable to obtain file status
ORA-205 signalled during: ALTER DATABASE  MOUNT...
ORA-00301: error in adding log file '/home/oracle/oracle/oradata/testdb/redo01.l
og' - file cannot be created
ORA-27040: file create error
ORA-1501 signalled during: CREATE DATABASE db2
ORA-00200: control file could not be created
TEXT
--------------------------------------------------------------------------------
ORA-00202: control file: '/oracle/u01/app/oracle/product/10.2.0/db2/dbs/cntrldb2
.dbf'
ORA-27038: created file already exists
ORA-1501 signalled during: CREATE DATABASE db2
ORA-00200: control file could not be created
ORA-00202: control file: '/oracle/u01/app/oracle/product/10.2.0/db2/dbs/cntrldb2
.dbf'
ORA-27038: created file already exists
ORA-1501 signalled during: CREATE DATABASE db2