环境：LINUX AS 3＋ORA 9.2.4 ＋DATA GUARD
MAX LOGFILES ,RESETLOGS
问题描述：目前已经搭建好了基于归档日记传输的最大性能保护模式的DG，想把它改基于REDO 日记传输模式。在备库新建STANDBY REDO 的时候报错，示例如下：
SQL> alter database add standby logfile group 4
('/SERVER/ora9/oradata/ora9i/redo04.log') size 100M;
Database altered.
SQL> alter database add standby logfile group 5
('/SERVER/ora9/oradata/ora9i/redo05.log') size 100M;
Database altered.
SQL> alter database add standby logfile group 6
('/SERVER/ora9/oradata/ora9i/redo06.log') size 100M
*
ERROR at line 1:
ORA-01185: logfile group number 6 is invalid
SQL> alter database add standby logfile group 7
('/SERVER/ora9/oradata/ora9i/redo07.log') size 100M
*
ERROR at line 1:
ORA-01185: logfile group number 7 is invalid
出现以上这个错误是因为控制文件中限制了MAX LOGFILES 最大日志组数量。
像这种情况只能重建控制文件。
但这是DG环境，处理控制文件要特别的小心，如果搞不好就会DG环境被破坏，需要重建环境。（那样工作量就大了）
1.导出重建脚本
SQL> alter database backup controlfile to trace;
Database altered.
在新产生的Trace文件中可以看到下面的内容：
STARTUP NOMOUNT pfile=$ORACLE_HOME/dbs/initora9i.ora-as_primary
CREATE CONTROLFILE REUSE DATABASE "ORA9I"
RESETLOGS FORCE LOGGING ARCHIVELOG
-- SET STANDBY TO MAXIMIZE PERFORMANCE
MAXLOGFILES 10
MAXLOGMEMBERS 3
MAXDATAFILES 100
MAXINSTANCES 1
MAXLOGHISTORY 226
LOGFILE
GROUP 1 '/SERVER/ora9/oradata/ora9i/redo01.log' SIZE 100M,
GROUP 2 '/SERVER/ora9/oradata/ora9i/redo02.log' SIZE 100M,
GROUP 3 '/SERVER/ora9/oradata/ora9i/redo03.log' SIZE 100M
-- STANDBY LOGFILE
DATAFILE
'/SERVER/ora9/oradata/ora9i/system01.dbf',
'/SERVER/ora9/oradata/ora9i/undotbs01.dbf',
'/SERVER/ora9/oradata/ora9i/cwmlite01.dbf',
'/SERVER/ora9/oradata/ora9i/drsys01.dbf',
'/SERVER/ora9/oradata/ora9i/example01.dbf',
'/SERVER/ora9/oradata/ora9i/indx01.dbf',
'/SERVER/ora9/oradata/ora9i/odm01.dbf',
'/SERVER/ora9/oradata/ora9i/tools01.dbf',
'/SERVER/ora9/oradata/ora9i/user01.dbf',
'/SERVER/ora9/oradata/ora9i/xdb01.dbf',
'/SERVER/ora9/oradata/ora9i/data01.dbf',
'/SERVER/ora9/oradata/ora9i/chxi.dbf'
CHARACTER SET ZHS16GBK
;
注意：
(1)在CREATE CONTROLFILE REUSE DATABASE "ORA9I" RESETLOGS FORCE LOGGING ARCHIVELOG中间的RESETLOGS， 一定要改成NORESETLOGS，不然日志的序列就乱了。也备库的同步就会出现麻烦。
(2)更改MAXLOGFILES 10
2.在主库重建控制文件
SQL> shutdown immediate;
SQL> @recreatectl.sh
控制文件已创建.
SQL> shutdown immediate;
SQL> startup
数据库重起成功，并确认REDO LOG的SEQUENCE有没有被RESET：
SQL> select group#,sequence#,status from v$Log;
GROUP# SEQUENCE# STATUS
---------- ---------- ----------------
1 67 ACTIVE
2 66 INACTIVE
3 68 CURRENT
3.为备库重建控制文件
在主库上执行：
SQL> alter database create standby controlfile as ‘控制文件名和路径’
并传送到备份机上。
关闭备库，并用新的控制文件覆盖原来的控制文件（注意备份旧的控制文件）;
4.重起备库
SQL> startup nomount;
SQL> alter database mount standby database;
alter database mount standby database
*
ERROR at line 1:
ORA-01991: invalid password file
'/SERVER/ora9/product/9.2/dbs/orapwora9i'
提示密码文件也失效了。
解决：从主库再传一份过来，覆盖。
重启备库：
SQL> startup nomount;
SQL> alter database mount standby database;
SQL> alter database recover managed standby
database disconnect from session;
确认相关进程已经启动：
SQL> select process,status from v$managed_standby;
PROCESS STATUS
------- ------------
ARCH CONNECTED
ARCH CONNECTED
MRP0 WAIT_FOR_LOG
RFS RECEIVING
RFS ATTACHED
5.验证备库工作正常：
在主库作日志切换。并看备库是否接收正常。
SQL> alter system switch logfile;
查看备库是否接收到主库的日志并正确应用。
SELECT SEQUENCE#, FIRST_TIME, NEXT_TIME, APPLIED FROM V$ARCHIVED_LOG ORDER BY SEQUENCE#;
6.继续加REDO lOG GROUP
这是因为控制文件被重建过了，之前在备库中建立成功的两个REDO4，REDO5也已经被用了。在OS中删除。
[oracle@ora9-2 ora9i]$ rm redo04.log redo05.log
SQL> alter database add standby logfile group 4
('/SERVER/ora9/oradata/ora9i/redo04.log') size 100M;
Database altered.
SQL> alter database add standby logfile group 5
('/SERVER/ora9/oradata/ora9i/redo05.log') size 100M;
Database altered.
SQL> alter database add standby logfile group 6
('/SERVER/ora9/oradata/ora9i/redo06.log') size 100M;
Database altered.
SQL> alter database add standby logfile group 7
('/SERVER/ora9/oradata/ora9i/redo07.log') size 100M;
Database altered.
7.特殊情况
假如不能正常传输切换之间产生的日志，需要手动传输并注册到备库来进行恢复：
SQL> ALTER DATABASE REGISTER PHYSICAL LOGFILE
'/SERVER/ora9/primary-arc/ora9i_1_60.log';
SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;
8.完成