番外：Oracle 中关于 Control File 的备份说明

查看告警日志文件：

 1 [[email?protected] trace]$ pwd
 2 /u01/app/oracle/diag/rdbms/prod1/PROD1/trace
 3 [[email?protected] trace]$ tail -f 200 alert_PROD1.log 
 4 tail: cannot open ‘200’ for reading: No such file or directory
 5 ==> alert_PROD1.log <==
 6 ORACLE_BASE from environment = /u01/app/oracle
 7 Tue May 21 19:44:50 2019
 8 ALTER DATABASE   MOUNT
 9 Errors in file /u01/app/oracle/diag/rdbms/prod1/PROD1/trace/PROD1_ckpt_5026.trc:
10 ORA-00208: number of control file names exceeds limit of 8
11 System state dump requested by (instance=1,osid=5026 (CKPT)),summary=[abnormal instance termination].
12 System State dumped to trace file /u01/app/oracle/diag/rdbms/prod1/PROD1/trace/PROD1_diag_5014.trc
13 Dumping diagnostic data in directory=[cdmp_20190521194450],requested by (instance=1,summary=[abnormal instance termination].
14 CKPT (ospid: 5026): terminating the instance due to error 208
15 Instance terminated by CKPT,pid = 5026

看下第10行：ORA-00208: number of control file names exceeds limit of 8

所以，控制文件多路复用最多为“八路军 -?铁流两万五千里，直向着一个坚定的方向！苦斗十年锻炼成一支不可战胜的力量。”！

再来看下官方文档?11g Release 2 (11.2)?Database Reference 对此参数的描述：

CONTROL_FILES

Range of values：1 to 8 filenames

?

3. 控制文件的备份

3.1 TRACE备份

　　需要知道的是，严格意义上来说，这不是控制文件的备份，而是根据当前控制文件生成了一份 trace 跟踪文件，该文件里面记录了数据库结构的基本信息，而且trace出来的文件是可以直接查看的。

3.1.1 TRACE默认备份

SQL> alter database backup controlfile to trace;

Database altered.

默认情况下，放哪里了？可以根据日志文件查看到：

1 Tue May 21 20:07:53 2019
2 alter database backup controlfile to trace
3 Backup controlfile written to trace file /u01/app/oracle/diag/rdbms/prod1/PROD1/trace/PROD1_ora_6647.trc 4 Completed: alter database backup controlfile to trace

这个路径可以通过参数 dump 查询到：

SQL> show parameter dump

NAME                  TYPE   VALUE
--------------------- ------ -------------------------------------------
background_core_dump  string partial
background_dump_dest  string /u01/app/oracle/diag/rdbms/prod1/PROD1/trace
core_dump_dest        string /u01/app/oracle/diag/rdbms/prod1/PROD1/cdump
max_dump_file_size    string unlimited
shadow_core_dump      string partial
user_dump_dest        string /u01/app/oracle/diag/rdbms/prod1/PROD1/trace

（编辑：PHP编程网 - 湛江站长网）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!