Backup and Recovery
Backup Types
Logical
Cold
Hot
Physical
With
Without
Issues
–
–
–
–
Protect the database from numerous types of failures
Increase Mean-Time-Between-Failures (MTBF)
Decrease Mean-Time-To-Recover (MTTR)
Minimize data loss
Categories of Failures
– Statement failure
– Logic error in an application
– Attempt to enter bad data into the table
– Attempt an operation with insufficient
privileges
– Attempt an INSERT or UPDATE to a table,
causing an extent to be allocated,
but with insufficient free space
left in the tablespace
No Recovery
Needed
Categories of Failures
– Statement failure
– User process failure
– The user performed an abnormal disconnect
in the session.
– The user’s session was abnormally terminated.
– The user’s program raised an address
exception terminating the session.
No Recovery
Needed
PMON
Categories of Failures
– Statement failure
– User process failure
– User error
– Accidental DROP TABLE;
– Accidental TRUNCATE TABLE;
– Accidental DELETE / UPDATE;
Recovery
Needed
IMP Utility
Categories of Failures
–
–
–
–
Statement failure
User process failure
User error
Instance failure
– HardWare Problem on CPU / RAM
No Recovery
Needed
PMON SMON
Categories of Failures
–
–
–
–
–
Statement failure
User process failure
User error
Instance failure
Media failure
– HardWare Problem on I/O Device
Recovery
Needed
Physical
Requirements for Strategy
– Business requirements
• Evolutionary process
– Technical requirements
•
•
•
•
Hardware, software, man power and time
Database configurations
Transaction volume
Frequency of backups
– Operational requirements
• 7-day / 24-hour operations
• Testing and validating backups
Physical Backup Methods
No archive
mode
Archive
mode
Physical backup
ARCHIVELOG
Online redo log files
Group 1
Group 2
053
052
Archived log
file
052
ARC0
/disk1/archive/arch%s.arc
053
052
LOG_ARCHIVE_DEST
LOG_ARCHIVE_FORMAT
Enabling ARCHIVELOG
Mode
1
2
4
Startup mount
Init.ora
3
Shutdown normal or immediate
Alter database open
Control
file
Alter database ARCHIVELOG
6
5
Shutdown normal or
immediate
Full database backup
SHUTDOWN IMMEDIATE;
Physical Closed Database Backup
Data files
Control
files
Redo log
files
Password Parameter
files
file
HOST cp <files> /backup/
Online or
offline
storage
STARTUP OPEN;
Advantages of Physical Closed
Database Backups
– Conceptually simple
– Easy to perform
– Require little operator interaction
Physical Opened Database
Backup (1)
Online
redo
log files
Control
files
Online or
offline
storage
Parameter
files
Archived redo
log files
HOST cp <files> /backup/
Pwd file
Physical Opened Database
All tablespace data Backup (2)
Individual data
files
file
SQL> alter tablespace <name> begin backup;
Online or
offline
storage
Data files
HOST cp <files> /backup/
SQL> alter tablespace <name> end backup;
Advantages of Physical Opened
Database Backups
– Maintains high database availability
– Can be done at a tablespace or data file level
– Supports nonstop business operations
1
Archived log file
1
ARC0
Redo log
files
Data files
1
Control
file
2
2
Redo log
files
Data files
2
Control
file
Archived log file
1
ARC0
1
3
2
Redo log
files
Data files
3
Control
file
Archived log file
3
ARC0
1
2
4
4
Redo log
files
Data files
4
Control
file
Archived log file
3
ARC0
1
3
2
5
Archived log file
5
ARC0
4
Redo log
files
Data files
5
Control
file
5
5
Data files
Control
file
1
2
3
4
6
Archived log file
5
ARC0
6
Redo log
files
Data files
1
2
3
4
5
6
Control
file
5
5
Data files
Control
file
9
Archived log file
9
ARC0
8
Redo log
files
Data files
9
Control
file
5
5
Data files
Control
file
1
2
3
4
5
6
7
8
1
Shutdown
2
Startup Mount
3
O.S. Restore From Hot or Cold Physical BackUp DataFile (s)
4
9
9
9
5
8
4a
Applyed Archived Logs #5 #6 #7
Redo log
files
4b
Applyed On Line Logs #8 #9
9
Data files
Recover DataFile (s) Automatic
5
Alter DataBase Open
6
Shutdown Immediate
7
New Cold Physical BackUp
8
Startup Open
9
Control
file
S.C.N. System Change Number
Data files
Header
Control file
1
RedoRecord
Incremental Time Stamp
2
Unique Identified “Committed Version D.B.”
Log file #
Log file
Low SCN #
Higth SCN #
Logical Backup Methods
Oracle Export and Import
Utilities
• An interactive dialog
• The export page of the Data Manager within
Enterprise Manager
• The command line interface, by specifying
parameters
These utilities enable you to do the following:
– Archive historical data
– Save table definitions (with or without data) to protect
from user error failure
– Move data between machines and databases or versions
of the Oracle server
– Transport tablespaces between databases
Formato
Binario
Proprietario
Data
Base
Exp
Data
Base
Imp
File *.dmp
Export Concepts
Oracle Server
Generate SQL
commands
Two-Task
common
(TTC)
SQL
command
processing
Buffer
cache
manager
Dump file
TTC
buffer
Evaluating
buffer
Buffer
cache
1
Full
1a
2
Owner
3
Analyze blocks
Read blocks
Tables
Oracle9i Server
IncType Complete
1b
IncType Cumulative
1c
IncType Incremental
KEYWORD
DESCRIPTION
(DEFAULT)
----------------------------------------------------------------USERID
username/password
BUFFER
size of data buffer
FILE
LOG
PARFILE
FILESIZE
output files
(EXPDAT.DMP)
log file of screen output
parameter filename
maximum size of each dump file
COMPRESS
CONSISTENT
import into one extent
cross-table consistency
(Y)
(N)
GRANTS
INDEXES
ROWS
CONSTRAINTS
TRIGGERS
export
export
export
export
export
(Y)
(Y)
(Y)
(Y)
(Y)
FULL
OWNER
TABLES
export entire DataBase
list of owner usernames
list of table names
INCTYPE
DIRECT
STATISTICS
incremental export type
direct path
analyze objects
grants
indexes
data rows
constraints
triggers
(N)
(N)
(ESTIMATE)
Command-Line Method
> exp scott/tiger file=scott.dmp owner=scott grants=Y rows=Y
Export Messages
Export: Release 9.2.0.4.0 - Production on Fri Oct 30 09:35:3
(c) Copyright 2003 Oracle Corporation. All rights reserved.
Connected to: Oracle9i Enterprise Edition Release 9.2.0.4.0
With the Partitioning option
PL/SQL Release 9.2.0.4.0 - Production
Export done in WE8DEC character set and WE8DEC NCHAR charact
. exporting pre-schema procedural objects and actions
. exporting foreign function library names for user SCOTT
. exporting object type definitions for user SCOTT
About to export SCOTT’s objects ...
. exporting database links
. exporting sequence numbers
. exporting cluster definitions
. about to export SCOTT’s tables via Conventional Path ...
. . exporting table BONUS 0 rows exported
. . exporting table DEPT 4 rows exported
. . exporting table EMP 14 rows exported
IncType Complete
IncType Incremental -----> Exp IncType Generic
IncType Cumulative -----> Exp IncType Cumulative or Complete
Oracle Standby
Implementation
•
•
•
•
•
Fail over Solution
Disaster Recovery Solution (if remote)
Ease of implementation
Minimum impact on Production System
Read Only Standby Database
Overview of Managed Oracle Standby DB
Primary Instance
ARCH
Standby Instance
T.N.S.
Redo log
Recovery proc
DBWR
Arc log
Arc log
RFS
Primary DB
Standby DB
Primary
control file
Standby
control file
1
Recovery Mode
2
ReadOnly Mode
3
Activate