单机环境
select * from v$logfile;
select * from v$log;
alter database add logfile thread 1 group 4 ('/u01/oradata/EleDb/redo04.log') size 512m;
alter database add logfile thread 1 group 5 ('/u01/oradata/EleDb/redo05.log') size 512m;
alter database add logfile thread 1 group 6 ('/u01/oradata/EleDb/redo06.log') size 512m;
alter system switch logfile;
alter database drop logfile group 1;
alter database drop logfile group 2;
alter database drop logfile group 3;
去操作系统把原有的redolog删除。
RAC双机环境:
select * from v$logfile;
select * from v$log;
alter database add logfile thread 1 group 5 ('/oracle/oradata/redo05.log') size 100m;
alter database add logfile thread 2 group 6 ('/oracle/oradata/redo06.log') size 100m;
alter database add logfile thread 1 group 7 ('/oracle/oradata/redo07.log') size 100m;
alter database add logfile thread 2 group 8 ('/oracle/oradata/redo08.log') size 100m;
alter system switch logfile;
alter system switch logfile;
alter system switch logfile;
alter database drop logfile group 1;
alter database drop logfile group 2;
alter database drop logfile group 3;
alter database drop logfile group 4;
alter database add logfile thread 1 group 1('/oracle/oradata/redo01_new.log') size 100m;
alter database add logfile thread 2 group 2('/oracle/oradata/redo02_new.log') size 100m;
alter database add logfile thread 1 group 3('/oracle/oradata/redo03_new.log') size 100m;
alter database add logfile thread 2 group 4('/oracle/oradata/redo04_new.log') size 100m;