BI的数据库又挂了，服务器主板坏了，远程管理卡坏了、监控卡坏了、并且还坏了4块硬盘。导致操作系统上直接看不到数据库使用的磁盘分区，数据库直接就挂了。

而这时候，同事去机房发现磁盘没有故障，服务器没有报警，只是远程管理卡访问不了了，负责硬件的同事咨询DELL的售后，按照DELL售后说的重启服务器后，操作系统无法启动，4快硬盘亮了黄灯。

DELL的工程师上门检查后，确定是主板坏了，监控卡坏了，硬盘损坏不报警，硬件的同事不知道磁盘损坏，一直到已经坏了4快硬盘，彻底无法使用了才发现故障。

DELL的工程师帮助下，成功启动了操作系统，而且数据文件并没有损坏，貌似是两块热备盘起了作用，但这时硬盘并没有更换，已经不敢对磁盘进行大量的I/O操作了，这时候还是很危险的。

BI的数据库，数据文件一共3.4TB，经查询真实有效的数据只有1TB多一点，所以在尽量减少I/O操作的情况下，使用expdp的network_link的方式迁移数据，把数据直接通过db_link直接迁移到另一个备用的数据库中。

impdp system/oracle1 schemas=ODS network_link=DATA_TO_IVL EXCLUDE=index PARALLEL=4 logfile=ods.log

但是这种方式DB_LINK是不会迁移的，在导入数据时，发现因为缺少DB_LINK导致有很多包和存储过程编译报错。

ALTER PROCEDURE "DW"."P_GET_PGM_INV"   COMPILE     PLSQL_OPTIMIZE_LEVEL=  2    PLSQL_CODE_TYPE=  INTERPRETED    PLSQL_DEBUG=  TRUE    PLSCOPE_SETTINGS=  'IDENTIFIERS:NONE' REUSE SETTINGS TIMESTAMP '2018-01-27 21:12:16'
ORA-39082: Object type ALTER_PROCEDURE:"DW"."P_ZZG_TEST" created with compilation warnings
ORA-39082: Object type ALTER_PROCEDURE:"DW"."P_UPDATE_BIZ_UNT_CD_1" created with compilation warnings
ORA-39082: Object type ALTER_PROCEDURE:"DW"."P_UPDATE_BIZ_UNT_CD_2" created with compilation warnings
ORA-39082: Object type ALTER_PROCEDURE:"DW"."P_ZZG_TEST_CUSTOMER" created with compilation warnings
ORA-39082: Object type ALTER_PROCEDURE:"DW"."P_ZZG_TEST_CUSTOMER1" created with compilation warnings
ORA-39083: Object type ALTER_PROCEDURE failed to create with error:
ORA-04052: error occurred when looking up remote object CHGSHS.PLAN_RATE_WEEK_DETAIL@IVALUE
ORA-00604: error occurred at recursive SQL level 3
ORA-02019: connection description for remote database not found
Failing sql is:

经过查询，发现故障数据库中一共有20个DB_LINK，而新的数据库中只有使用NETWORK_LINK时创建的一个DB_LINK，而且手动创建出这些DB_LINK是可以的，但是我并不知道那些DB_LINK指向的数据库的用户密码，只能去故障数据库把DB_LINK导出来，再到新数据库导入，这样就不需要密码了。

因为只需要导出DB_LINK就可以，这里使用了INCLUDE选项。

[oracle@HUIMAIBI dpdump]$ expdp system/oracle1 dumpfile=dblink.dmp directory=DATA_PUMP_DIR full=Y include=db_link 
Export: Release 11.2.0.4.0 - Production on Sun Jan 28 04:47:23 2018

Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
;;; 
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
Starting "SYSTEM"."SYS_EXPORT_FULL_01":  system/******** dumpfile=dblink.dmp directory=DATA_PUMP_DIR full=Y include=db_link 
Estimate in progress using BLOCKS method...
Total estimation using BLOCKS method: 0 KB
Processing object type DATABASE_EXPORT/SCHEMA/DB_LINK
Master table "SYSTEM"."SYS_EXPORT_FULL_01" successfully loaded/unloaded
******************************************************************************
Dump file set for SYSTEM.SYS_EXPORT_FULL_01 is:
  /u01/app/oracle/admin/huimaibi/dpdump/dblink.dmp
Job "SYSTEM"."SYS_EXPORT_FULL_01" successfully completed at Sun Jan 28 04:47:42 2018 elapsed 0 00:00:17

新的数据库导入就会把DB_LINK直接导入了。

[oracle@SL010A-IVDB01 u01]$ impdp system/oracle1 directory=expbk dumpfile=dblink.dmp 

Import: Release 11.2.0.4.0 - Production on Sun Jan 28 04:49:48 2018

Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.

Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
Master table "SYSTEM"."SYS_IMPORT_FULL_01" successfully loaded/unloaded
Starting "SYSTEM"."SYS_IMPORT_FULL_01":  system/******** directory=expbk dumpfile=dblink.dmp 
Processing object type DATABASE_EXPORT/SCHEMA/DB_LINK
ORA-31684: Object type DB_LINK:"DW"."CX" already exists
Job "SYSTEM"."SYS_IMPORT_FULL_01" completed with 1 error(s) at Sun Jan 28 04:49:53 2018 elapsed 0 00:00:03

导入完成后，去编译一下失效对象就可以了。

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