Oracle9i DBA II: BackupRecovery and Network Administration

1
Chapter 7Performing Backup Operations with
Recovery Manager
2
Chapter Objectives

• Identify the tablespaces and data files
  associated with the target database using the
  REPORT command
• Manually allocate a channel to perform backup
  operations

3
Chapter Objectives (Cont.)

• Include a snapshot of the control file when
  backing up a tablespace
• Distinguish between a full backup and a Level 0
  backup
• Explain the difference between differential and
  cumulative incremental backup strategies

4
Chapter Objectives (Cont.)

• Perform a Level 0 backup of multiple tablespaces
  using the BACKUP command
• Describe the difference between an image copy and
  a backup of a data file

5
Basic Features

• Can create
• Image copies - exact duplicate of entire file
• Incremental backups
• Used blocks only
• Changed blocks only

6
Report Command

• Provides information regarding repository contents

7
Report Example
8
Report Database Schema
9
RMAN Command Types

• Stand-alone command
• Single command
• Executes immediately
• Job command
• Block of commands
• Enclosed in curly braces
• Each command terminated by semicolon
• Executed in sequence

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Job Command Example
11
ALLOCATE Command
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ALLOCATE Command Keywords

• CHANNEL names the channel
• DEVICE TYPE
• DISK magnetic disk
• SBT_TAPE or TAPE magnetic tape

13
BACKUP Command Options
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BACKUP Command Options (cont)
15
Full vs. Whole Backup

• Full
• Creates copy of all used data blocks
• Whole
• Backup of all files needed in the event that
  recovery becomes necessary

16
Elements of the FORMAT Option
17
Output of Executed BACKUP Command
18
Example Backup of Archived Redo Log Files
19
Incremental Backup

• Five backup levels
• Level 0
• Copies same data as full backup
• Serves as the base level of incremental backup
  strategy
• Levels 1-4
• Backup changed blocks since previous incremental
  backup

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Example Level 0 Backup of Tablespaces
21
Differential vs. Cumulative

• Differential incremental backup
• Copies data blocks changes after last Level n or
  lower backup
• Default
• Cumulative incremental backup
• Copies data blocks changes after last Level n-1
  or lower backup
• Requires CUMULATIVE keyword

22
Differential Incremental Backup
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Cumulative Incremental Backup
24
Incremental Backups and Archiving Modes

• ARCHIVELOG database
• Can be open
• SCN used to identify changed data blocks
• NOARCHIVELOG database
• Requires SCN in all files to be consistent
• Database must be mounted, but not opened

25
Image Copies

• Creates exact duplicate of file
• Similar to operating system copy
• Can be used as part of a full or incremental
  backup strategy
• RMAN automatically checks for corruption when
  created

26
COPY Command Syntax
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COPY Command Example
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Chapter Summary

• RMAN can be used to back up changed data blocks
  or to create an image copy
• REPORT command can identify data files meeting
  certain criteria
• Stand-alone commands execute immediately job
  commands executed using RUN command

29
Chapter Summary (Cont.)

• ALLOCATE command used to manually allocate a
  channel
• Full backup creates copy of all used data blocks
  in a file
• Differential backs up changes since last Level n
  or lower Cumulative backs up changes since last
  Level n -1 or lower

30
Chapter Summary (Cont.)

• Level 0 serves as baseline backs up same data
  blocks as a full backup
• Full backup cannot serve as a baseline
• Cumulative takes longer than differential
  backups, but recovery is faster
• Image copy is an exact copy of file, including
  empty data blocks