1.1 online redolog file 丢失
联机Redo日志是Oracle数据库中比较核心的文件，当Redo日志文件异常之后，数据库就无法正常启动，而且有丢失据的风险，强烈建议在条件允许的情况下，对Redo日志进行多路镜像。需要注意的是，RMAN不能备份联机Redo日志文件。所以，联机Redo日志一旦出现故障，则只能进行清除日志了。清除日志文件即表明可以重用该文件。
1.1.1 数据库归档/非归档模式下inactive redo异常ORA-00316 ORA-00327
1.1.1.1 例一
SQL> startup mount
ORACLE instance started.
Total System Global Area 260046848 bytes
Fixed Size 1266896 bytes
Variable Size 83888944 bytes
Database Buffers 167772160 bytes
Redo Buffers 7118848 bytes
Database mounted.
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-00316: log 2 of thread 1, type in header is not log file
ORA-00312: online log 2 thread 1: '/u01/oracle/oradata/XFF/redo02.log'
SQL> col member for a40
SQL> set lines 120
SQL> SELECT thread#,
2 a.sequence#,
3 a.group#,
4 TO_CHAR (first_change#, '9999999999999999') "SCN",
5 a.status,
6 MEMBER
7 FROM v$log a, v$logfile b
8 WHERE a.group# = B.GROUP#
9 ORDER BY a.sequence# DESC;
THREAD# SEQUENCE# GROUP# SCN STATUS MEMBER
---------- ---------- ---------- ----------------- ---------------- -----------------------------------
1 15 3 665697 CURRENT /u01/oracle/oradata/XFF/redo03.log
1 14 2 645619 INACTIVE /u01/oracle/oradata/XFF/redo02.log
1 13 1 625540 INACTIVE /u01/oracle/oradata/XFF/redo01.log
SQL> ALTER DATABASE CLEAR LOGFILE GROUP 2;
Database altered.
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-00327: log 2 of thread 1, physical size less than needed
ORA-00312: online log 2 thread 1: '/u01/oracle/oradata/XFF/redo02.log'
SQL> alter database drop logfile group 2;
Database altered.
SQL> alter database open;
Database altered.
SQL> alter database add logfile group 2 ('/u01/oracle/oradata/XFF/redo02.log') size 50M reuse;
Database altered.
1.1.1.2 例二
[oracle@orcltest ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Wed May 6 13:46:16 2015
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL> col member for a50
SQL> set lines 120
SQL> SELECT thread#,
2 a.sequence#,
3 a.group#,
4 TO_CHAR (first_change#, '9999999999999999') "SCN",
5 a.status,
6 MEMBER
7 FROM v$log a, v$logfile b
8 WHERE a.group# = B.GROUP#
9 ORDER BY a.sequence# DESC;
THREAD# SEQUENCE# GROUP# SCN STATUS MEMBER
---------- ---------- ---------- ----------------- ---------------- --------------------------------------------------
1 16 3 1209020 CURRENT /u02/app/oracle/oradata/oratest/redo03.log
1 15 1 1209017 INACTIVE /u02/app/oracle/oradata/oratest/redo01.log
1 14 2 1209012 INACTIVE /u02/app/oracle/oradata/oratest/redo02.log
SQL> ! rm -rf /u02/app/oracle/oradata/oratest/redo01.log
SQL>
SQL> startup force;
ORACLE instance started.
Total System Global Area 409194496 bytes
Fixed Size 2228864 bytes
Variable Size 297799040 bytes
Database Buffers 100663296 bytes
Redo Buffers 8503296 bytes
Database mounted.
ORA-03113: end-of-file on communication channel
Process ID: 15390
Session ID: 125 Serial number: 5
SQL>
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
告警日志：
Errors in file /u02/app/oracle/diag/rdbms/oratest/oratest/trace/oratest_lgwr_15484.trc:
ORA-00313: open failed for members of log group 1 of thread 1
ORA-00312: online log 1 thread 1: '/u02/app/oracle/oradata/oratest/redo01.log'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3
[oracle@orcltest ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Wed May 6 13:48:39 2015
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup mount;
ORACLE instance started.
Total System Global Area 409194496 bytes
Fixed Size 2228864 bytes
Variable Size 297799040 bytes
Database Buffers 100663296 bytes
Redo Buffers 8503296 bytes
Database mounted.
SQL> alter database clear logfile group 1;
Database altered.
SQL> alter database open;
Database altered.
SQL> col member for a50
SQL> set lines 120
SQL> SELECT thread#,
2 a.sequence#,
3 a.group#,
4 TO_CHAR (first_change#, '9999999999999999') "SCN",
5 a.status,
6 MEMBER
7 FROM v$log a, v$logfile b
8 WHERE a.group# = B.GROUP#
9 ORDER BY a.sequence# DESC;
THREAD# SEQUENCE# GROUP# SCN STATUS MEMBER
---------- ---------- ---------- ----------------- ---------------- --------------------------------------------------
1 17 1 1229024 CURRENT /u02/app/oracle/oradata/oratest/redo01.log
1 16 3 1209020 INACTIVE /u02/app/oracle/oradata/oratest/redo03.log
1 14 2 1209012 INACTIVE /u02/app/oracle/oradata/oratest/redo02.log
SQL>
1.1.2 正常关闭数据库current redo异常ORA-00316 ORA-01623
1.1.2.1 例一
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-00316: log 1 of thread 1, type in header is not log file
ORA-00312: online log 1 thread 1: '/u01/oracle/oradata/XFF/redo01.log'
SQL> SELECT thread#,
2 a.sequence#,
3 a.group#,
4 TO_CHAR (first_change#, '9999999999999999') "SCN",
5 a.status,