SQL> select group#,sequence#,bytes,archived,status from v$log;
GROUP# SEQUENCE#
BYTES ARC STATUS
---------- ---------- ---------- --- ----------------
1
16
52428800 NO CURRENT
2
14
52428800 YES INACTIVE
3
15
52428800 YES INACTIVE
SQL> alter database add logfile group 4 '/ora/app/oracle/oradata/inforln/redo04.log' size 6G;
Database altered.
SQL> alter database add logfile group 5 '/ora/app/oracle/oradata/inforln/redo05.log' size 6G;
Database altered.
SQL> alter database add logfile group 6 '/ora/app/oracle/oradata/inforln/redo06.log' size 6G;
Database altered.
SQL> select group#,sequence#,bytes,archived,status from v$log;
GROUP# SEQUENCE#
BYTES ARC STATUS
---------- ---------- ---------- --- ----------------
1
16
52428800 NO CURRENT
2
14
52428800 YES INACTIVE
3
15
52428800 YES INACTIVE
4
0 6442450944 YES UNUSED
5
0 6442450944 YES UNUSED
6
0 6442450944 YES UNUSED
6 rows selected.
SQL> alter database drop logfile group 2;
Database altered.
SQL> select group#,sequence#,bytes,archived,status from v$log;
GROUP# SEQUENCE#
BYTES ARC STATUS
---------- ---------- ---------- --- ----------------
1
16
52428800 NO CURRENT
3
15
52428800 YES INACTIVE
4
0 6442450944 YES UNUSED
5
0 6442450944 YES UNUSED
6
0 6442450944 YES UNUSED
SQL> alter database add logfile group 2 '/ora/app/oracle/oradata/inforln/redo02.log' size 6G;
alter database add logfile group 2 '/ora/app/oracle/oradata/inforln/redo02.log' size 6G
*
ERROR at line 1:
ORA-00301: error in adding log file
'/ora/app/oracle/oradata/inforln/redo02.log' - file cannot be created
ORA-27038: created file already exists
Additional information: 1
$ rename the redo file
$ mv redo02.log redo02.old.log
SQL> alter database add logfile group 2 '/ora/app/oracle/oradata/inforln/redo02.log' size 6G;
Database altered.
SQL> select group#,sequence#,bytes,archived,status from v$log;
GROUP# SEQUENCE#
BYTES ARC STATUS
---------- ---------- ---------- --- ----------------
1
16
52428800 NO CURRENT
2
0 6442450944 YES UNUSED
3
15
52428800 YES INACTIVE
4
0 6442450944 YES UNUSED
5
0 6442450944 YES UNUSED
6
0 6442450944 YES UNUSED
6 rows selected.
SQL> alter database drop logfile group 3;
Database altered.
$ rename the redo file
$ mv redo03.log redo03.old.log
SQL> alter database add logfile group 3 '/ora/app/oracle/oradata/inforln/redo03.log' size 6G;
Database altered.
SQL> select group#,sequence#,bytes,archived,status from v$log;
GROUP# SEQUENCE#
BYTES ARC STATUS
---------- ---------- ---------- --- ----------------
1
16
52428800 NO CURRENT
2
0 6442450944 YES UNUSED
3
0 6442450944 YES UNUSED
4
0 6442450944 YES UNUSED
5
0 6442450944 YES UNUSED
6
0 6442450944 YES UNUSED
6 rows selected.
SQL> alter system switch logfile;
System altered.
SQL> select group#,sequence#,bytes,archived,status from v$log;
GROUP# SEQUENCE#
BYTES ARC STATUS
---------- ---------- ---------- --- ----------------
1
16
52428800 YES ACTIVE
2
17 6442450944 NO CURRENT
3
0 6442450944 YES UNUSED
4
0 6442450944 YES UNUSED
5
0 6442450944 YES UNUSED
6
0 6442450944 YES UNUSED
6 rows selected.
SQL> alter database drop logfile group 1;
alter database drop logfile group 1
*
ERROR at line 1:
ORA-01624: log 1 needed for crash recovery of instance inforln (thread 1)
ORA-00312: online log 1 thread 1: '/ora/app/oracle/oradata/inforln/redo01.log'
SQL> alter system checkpoint global;
System altered.
SQL> select group#,sequence#,bytes,archived,status from v$log;
GROUP# SEQUENCE#
BYTES ARC STATUS
---------- ---------- ---------- --- ----------------
1
16
52428800 YES INACTIVE
2
17 6442450944 NO CURRENT
3
0 6442450944 YES UNUSED
4
0 6442450944 YES UNUSED
5
0 6442450944 YES UNUSED
6
0 6442450944 YES UNUSED
6 rows selected.
SQL> alter database drop logfile group 1;
Database altered.
$ rename the redo file
$ mv redo01.log redo01.old.log
SQL> alter database add logfile group 1 '/ora/app/oracle/oradata/inforln/redo01.log' size 6G;
Database altered.
SQL> select group#,sequence#,bytes,archived,status from v$log;
GROUP# SEQUENCE#
BYTES ARC STATUS
---------- ---------- ---------- --- ----------------
1
0 6442450944 YES UNUSED
2
17 6442450944 NO CURRENT
3
0 6442450944 YES UNUSED
4
0 6442450944 YES UNUSED
5
0 6442450944 YES UNUSED
6
0 6442450944 YES UNUSED
6 rows selected.
SQL>
