由于机房断电,导致数据库异常down 机，重启的时候报错：
Errors in file /opt/oracle/admin/aliuid/bdump/aliuid_arc1_19960.trc:
ORA-00354: corrupt redo log block header
ORA-00353: log corruption near block 26402 change 0 time 02/14/2012 01:32:17
ORA-00312: online log 1 thread 1: '/opt/oracle/oradata/aliuid/redo01.log'
Mon Feb 20 15:57:00 2012
Errors in file /opt/oracle/admin/aliuid/udump/aliuid_ora_20140.trc:
ORA-00600: internal error code, arguments: [2662], [0], [94450252], [0], [94509989], [8388625], [], []
ORA-00354 ,ORA-00353,ORA-00312 报错是由于在线日志块损坏导致！
针对日志坏块，我使用了 _disable_logging 隐含参数，然后清理了在线日志！
@>alter system set "_disable_logging"=false scope=both;
System altered.
@>alter database clear unarchived logfile '/opt/oracle/oradata/aliuid/redo01.log';
Database altered.
@>select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------------
1 1 0 104857600 1 YES UNUSED 94410240 2012-02-13 21:35:38
2 1 381 104857600 1 NO INACTIVE 94430242 2012-02-20 15:35:43
3 1 382 104857600 1 NO CURRENT 94450247 2012-02-20 15:56:57
@>exit
oracle@c9e016r3ectk1xl67j8p:aliuid /home/oracle>sqlplus "/as sysdba"
@>startup mount;
ORACLE instance started.
Total System Global Area 3693056168 bytes
Fixed Size 745640 bytes
Variable Size 469762048 bytes
Database Buffers 3221225472 bytes
Redo Buffers 1323008 bytes
Database mounted.
@>
@>col name for a60
@> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------------
1 1 383 104857600 1 NO CURRENT 94470251 2012-02-20 20:12:56
2 1 381 104857600 1 YES INACTIVE 94430242 2012-02-20 15:35:43
3 1 382 104857600 1 YES INACTIVE 94450247 2012-02-20 15:56:57
@>alter database clear unarchived logfile '/opt/oracle/oradata/aliuid/redo01.log';
alter database clear unarchived logfile '/opt/oracle/oradata/aliuid/redo01.log'
*
ERROR at line 1:
ORA-01624: log 1 needed for crash recovery of thread 1
ORA-00312: online log 1 thread 1: '/opt/oracle/oradata/aliuid/redo01.log'
@>alter database clear unarchived logfile '/opt/oracle/oradata/aliuid/redo02.log';
Database altered.
@>col name for a60
@> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------------
1 1 383 104857600 1 NO CURRENT 94470251 2012-02-20 20:12:56
2 1 0 104857600 1 YES UNUSED 94430242 2012-02-20 15:35:43
3 1 382 104857600 1 YES INACTIVE 94450247 2012-02-20 15:56:57
@>alter database clear unarchived logfile '/opt/oracle/oradata/aliuid/redo03.log';
Database altered.
@>alter database open;
alter database open
*
ERROR at line 1:
ORA-00603: ORACLE server session terminated by fatal error
oracle@c9e016r3ectk1xl67j8p:aliuid /home/oracle>sqlplus "/as sysdba"
@>startup mount;
ORACLE instance started.
Total System Global Area 3693056168 bytes
Fixed Size 745640 bytes
Variable Size 469762048 bytes
Database Buffers 3221225472 bytes
Redo Buffers 1323008 bytes
Database mounted.
@>col name for a60
@> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------------
1 1 383 104857600 1 YES INACTIVE 94470251 2012-02-20 20:12:56
2 1 384 104857600 1 NO CURRENT 94490254 2012-02-20 20:15:36
3 1 0 104857600 1 YES UNUSED 94450247 2012-02-20 15:56:57
ORA-600 [2662] "Block SCN is ahead of Current SCN"，说明当前数据库的数据块的SCN早于当前的SCN，主要是和存储在UGA变量中的dependent SCN进行比较，如果当前的SCN小于它，数据库就会产生这个ORA-600 [2662]的错误了。这个错误一共有五个参数，分别代表不同的含义，
ORA-600 [2662] [a] [b] [c] [d] [e]
Arg [a] Current SCN WRAP
Arg [b] Current SCN BASE
Arg [c] dependent SCN WRAP
Arg [d] dependent SCN BASE
Arg [e] Where present this is the DBA where the dependent SCN came from.
当前的报错是当前的SCN=94450252 小于dependent SCN 94509989！
文档上介绍
"1.数据库crash后设置了_DISABLE_LOGGING隐含参数
2.硬件错误引起数据库没法写控制文件和重做日志文件
3.错误的部分恢复数据库
4.恢复了控制文件但是没有使用recover database using backup controlfile进行恢复
5.使用隐含参数_ALLOW_RESETLOGS_CORRUPTION后resetlogs打开数据库
6.在并行服务器环境中DLM存在问题 "
参考了eygle 的文章 使用ADJUST_SCN事件来调整当前的SCN，使其大于dependent SCN!(然后保证数据库可以全库的导出，然后重建数据库导入数据)
@>alter session set events 'IMMEDIATE trace name ADJUST_SCN level 1';
ERROR:
ORA-00600: internal error code, arguments: [kcsadjn1], [], [], [], [], [], [], []
这一步执行错误，本应该在mount状态执行此命令的！eygle的文章：
增进SCN有两种常用方法:
1.通过immediate trace name方式(在数据库Open状态下)
alter session set events 'IMMEDIATE trace name ADJUST_SCN level x';
2.通过10015事件(在数据库无法打开，mount状态下)
alter session set events '10015 trace name adjust_scn level x';
注:level 1为增进SCN 10亿 (1 billion) (1024*1024*1024),通常Level 1已经足够。也可以根据实际情况适当调整。
本例由于数据库无法打开，只能使用的二种方法。
之后多次shutdown ，startup 之后 scn 的报错消失，出现关于undo的ora-600 [4193] 报错，次错误是和undo表空间相关的报错
“ While backing out an undo record (i.e. at the time of rollback) we found a transaction id mis-match indicating either a corruption in the rollback segment or corruption in an object which the rollback segment is trying to apply undo records on.This would indicate corrupted rollback segment.”
其解决办法是(针对非open状态的数据库)
1 在pfile里修改
*.undo_management='MANUAL'
*.rollback_segments='SYSTEM'
2 重新启动数据库
3 drop tablespace undotbs1 including contents and datafiles;
4 create undo tablespace undotbs2 datafile '/opt/oracle/oradata/aliuid/undotbs2.dbf' size 500m;
5 shutdown immediate;
6 重新修改数据库参数文件为新的undo表空间！
*.undo_management='AUTO'
*.undo_retention=900
*.undo_tablespace='UNDOTBS2'
7 创建新的spfile文件并再次重新启动数据库
最终数据库问题解决！
参考文章
