📌  相关文章
📜  DB2-备份和恢复

📅  最后修改于: 2020-11-28 13:26:30             🧑  作者: Mango

本章介绍数据库的备份和还原方法。

后备

介绍

备份和恢复方法旨在确保我们的信息安全。在使用备份和恢复实用程序的命令行界面(CLI)或图形用户界面(GUI)中，您可以备份或还原DB2 UDB中数据库的数据。

记录中

日志文件包含错误日志，这些错误日志用于从应用程序错误中恢复。日志记录了数据库中的更改记录。日志记录分为以下两种：

循环记录

这是一种在需要分配新的事务日志文件时覆盖旧事务日志的方法，从而擦除日志文件的序列并重新使用它们。您只能在离线模式下进行完整备份。即，数据库必须脱机才能进行完整备份。

存档记录

此模式支持使用称为前滚恢复的日志文件进行联机备份和数据库恢复。通过将logretain或userexit设置为ON，可以将备份模式从循环更改为存档。对于归档日志记录，备份设置数据库需要一个对于DB2进程可写的目录。

后备

使用备份命令可以复制整个数据库。该备份副本包括数据库系统文件，数据文件，日志文件，控制信息等。

您既可以在离线状态下也可以在线进行备份。

离线备份

语法： [列出活动的应用程序/数据库]

db2 list application

输出：

Auth Id  Application    Appl.      Application Id                                                
DB       # of   
         Name           Handle              
Name    Agents  
-------- -------------- ---------- ---------------------
----------------------------------------- -------- -----  
DB2INST1 db2bp          39         
*LOCAL.db2inst1.140722043938                                   
ONE      1

语法： [强制使用app进行申请。已处理的ID]

db2 "force application (39)"

输出：

DB20000I  The FORCE APPLICATION command completed 
successfully.  

DB21024I  This command is asynchronous and may not 
be effective immediately.

语法： [终止数据库连接]

db2 terminate

语法： [停用数据库]

db2 deactivate database one

语法： [获取备份文件]

db2 backup database  to

例：

db2 backup database one to /home/db2inst1/

输出：

Backup successful. The timestamp for this backup image is : 
20140722105345

在线备份

首先，您需要将模式从循环日志记录更改为存档日志记录。

语法： [检查数据库是否使用循环日志或归档日志]

db2 get db cfg for one | grep LOGARCH

输出：

First log archive method (LOGARCHMETH1) = OFF  
 Archive compression for logarchmeth1  (LOGARCHCOMPR1) = OFF 
 Options for logarchmeth1              (LOGARCHOPT1) =   
 Second log archive method             (LOGARCHMETH2) = OFF  
 Archive compression for logarchmeth2  (LOGARCHCOMPR2) = OFF  
 Options for logarchmeth2              (LOGARCHOPT2) =

在上面的输出中，突出显示的值为off模式下的[logarchmeth1和logarchmeth2]，这意味着当前数据库处于“ CIRCULLAR LOGGING”模式。如果需要使用“ ARCHIVE LOGGING”模式，则需要更改或添加配置文件中存在的变量logarchmeth1和logarchmeth2的路径。

使用所需的归档目录更新logarchmeth1

语法： [创建目录]

mkdir backup 
mkdir backup/ArchiveDest

语法： [为文件夹提供用户权限]

chown db2inst1:db2iadm1 backup/ArchiveDest

语法： [更新配置LOGARCHMETH1]

db2 update database configuration for one using LOGARCHMETH1 
'DISK:/home/db2inst1/backup/ArchiveDest'

为了安全起见，您可以进行离线备份，激活数据库并连接到数据库。

语法： [进行在线备份]

db2 backup database one online to 
/home/db2inst1/onlinebackup/ compress include logs

输出：

db2 backup database one online to 
/home/db2inst1/onlinebackup/ compress include logs

使用以下命令验证备份文件：

句法：

db2ckbkp

例：

db2ckbkp 
/home/db2inst1/ONE.0.db2inst1.DBPART000.20140722112743.001

列出备份文件的历史记录

句法：

db2 list history backup all for one

输出：

List History File for one 
  
Number of matching file entries = 4 
 
Op Obj Timestamp+Sequence Type Dev Earliest Log Current Log  
Backup ID  
 -- --- ------------------ ---- --- ------------ ------------ 
 --------------
  B  D  20140722105345001   F    D  S0000000.LOG S0000000.LOG 

 ------------------------------------------------------------ 
 ----------------   
 
 Contains 4 tablespace(s): 
 00001 SYSCATSPACE  
 
 00002 USERSPACE1
 
 00003 SYSTOOLSPACE 
 
 00004 TS1 
  ------------------------------------------------------------ 
  ---------------- 
  Comment: DB2 BACKUP ONE OFFLINE  
  
 Start Time: 20140722105345  
 
   End Time: 20140722105347
   
     Status: A
 ------------------------------------------------------------ 
 ---------------- 
 EID: 3 Location: /home/db2inst1 

 
 Op Obj Timestamp+Sequence Type Dev Earliest Log Current Log  
 Backup ID
 -- --- ------------------ ---- --- ------------ ------------ 
 --------------  
  B  D  20140722112239000   N       S0000000.LOG S0000000.LOG   
 ------------------------------------------------------------ 
 ------------------------------------------------------------- 
 ------------------------------- 
 
 Comment: DB2 BACKUP ONE ONLINE  
 
 Start Time: 20140722112239 
 
   End Time: 20140722112240  
   
     Status: A 
 ------------------------------------------------------------ 
 ----------------  
  EID: 4 Location: 
SQLCA Information 
 
 sqlcaid : SQLCA     sqlcabc: 136   sqlcode: -2413   sqlerrml: 0 
 
 sqlerrmc:   
 sqlerrp : sqlubIni  
 sqlerrd : (1) 0                (2) 0                (3) 0 
 
           (4) 0                (5) 0                (6) 0  
           
 sqlwarn : (1)      (2)      (3)      (4)        (5)       (6)  
 
           (7)      (8)      (9)      (10)       (11)  
 sqlstate: 
 
 Op Obj Timestamp+Sequence Type Dev Earliest Log Current Log  
 Backup ID
  -- --- ------------------ ---- --- ------------ ------------ 
  -------------- 
   B  D  20140722112743001   F    D  S0000000.LOG S0000000.LOG   
 
 ------------------------------------------------------------ 
 ---------------- 
 Contains 4 tablespace(s): 
 
 00001 SYSCATSPACE 
 
 00002 USERSPACE1 
 
 00003 SYSTOOLSPACE 
 
 00004 TS1
  ------------------------------------------------------------- 
  ---------------- 
  Comment: DB2 BACKUP ONE OFFLINE 
  
 Start Time: 20140722112743 
 
   End Time: 20140722112743 
   
     Status: A 
 ------------------------------------------------------------- 
  ---------------- 
 EID: 5 Location: /home/db2inst1 
 
 Op Obj Timestamp+Sequence Type Dev Earliest Log Current Log 
 Backup ID   
  ------------------------------------------------------------- 
  ----------------
  
R  D  20140722114519001   F                                
20140722112743 

 ------------------------------------------------------------ 
 ----------------  
 Contains 4 tablespace(s):  
 
 00001 SYSCATSPACE 
 
  00002 USERSPACE1 
  
 00003 SYSTOOLSPACE  
 
 00004 TS1
 ------------------------------------------------------------ 
 ----------------  
Comment: RESTORE ONE WITH RF
  
 Start Time: 20140722114519 
 
   End Time: 20140722115015  
     Status: A  
     
 ------------------------------------------------------------ 
 ----------------  
  EID: 6 Location:

从备份还原数据库

要从备份文件还原数据库，您需要遵循给定的语法：

句法：

db2 restore database  from  
taken at

例：

db2 restore database one from /home/db2inst1/ taken at 
20140722112743

输出：

SQL2523W  Warning!  Restoring to an existing database that is 
different from  
 
the database on the backup image, but have matching names. 
The target database  
 
will be overwritten by the backup version.  The Roll-forward 
recovery logs

associated with the target database will be deleted.  

Do you want to continue ? (y/n) y 
 
DB20000I  The RESTORE DATABASE command completed successfully.

前滚位于日志目录中的所有日志，包括磁盘驱动器发生故障之前的最新更改。

句法：

db2 rollforward db  to end of logs and stop

例：

db2 rollforward db one to end of logs and stop

输出：

Rollforward Status  
 Input database alias                   = one  
 Number of members have returned status = 1  
 Member ID                              = 0  
 Rollforward status                     = not pending  
 Next log file to be read               =  
 Log files processed                    = S0000000.LOG - 
 S0000001.LOG  
 Last committed transaction            = 2014-07-22- 
 06.00.33.000000 UTC  
DB20000I  The ROLLFORWARD command completed successfully.