個人自行閱讀時候，翻譯的文檔。因為比較渣，如果有更合理或者錯誤的地方煩勞告知，我會做修改。
This chapter explains Oracle Database backup and recovery and summarizes the Oracle solutions. This chapter contains the following topics:
? Purpose of Backup and Recovery
? Oracle Backup and Recovery Solutions
? About Oracle Flashback Technology
? About Data Recovery Advisor
? RMAN and Oracle Enterprise Manager Cloud Control
? About Zero Data Loss Recovery Appliance
? Backup and Recovery Documentation Roadmap
譯文:
這篇章節涵蓋了Oracle 數據庫備份和恢復以及Oracle解決方案的簡要概述，章節涵蓋了以下主題
? 備份和恢復的目的
? Oracle備份和恢復的解決方案
? 關于Oracle 閃回技術
? 關于數據恢復建議
? RMAN和Oracle企業云管理控制
? 關于零數據丟失恢復配置
? 備份和恢復文檔路線圖
Purpose of Backup and Recovery
As a backup administrator, your principal duty is to devise, implement, and manage a backup and recovery strategy. In general, the purpose of a backup and recovery
strategy is to protect the database against data loss and reconstruct the database after data loss. Typically, backup administration tasks include the following:
? Planning and testing responses to different kinds of failures
? Configuring the database environment for backup and recovery
? Setting up a backup schedule
? Monitoring the backup and recovery environment
? Troubleshooting backup problems
? Recovering from data loss if the need arises
譯文:
備份和恢復的目的
作為一個備份管理員,你最主要的責任就是設計,實施和管理一個備份和恢復策略.通常,備份和恢復策略是為了防止數據丟失和在數據丟失后進行重構數據庫.通常，備份管理的任務包含以下
? 計劃和測試響應不同的失敗
? 配置數據庫備份和恢復環境
? 建立一個備份計劃
? 監控備份和恢復環境
? 解決備份問題
? 在需要的時候恢復數據丟失
As a backup administrator, you may also be asked to perform other duties that are
related to backup and recovery:
? Data archival, which involves creating a database copy for long-term storage
? Data transfer, which involves moving data from one database or one host to
another
The purpose of this manual is to explain how to perform the preceding tasks.
譯文:
作為一個備份管理員,你也可能會被要求執行其他的備份和恢復的職責
? 數據歸檔,涉及到長期存儲數據庫的拷貝
? 數據傳輸,解決數據從一個數據庫或者一臺主機移到另一臺
手冊的目的是解析如何執行前面的任務
About Data Protection
As a backup administrator, your primary job is making and monitoring backups for
data protection. A backup is a copy of data of a database that you can use to
reconstruct data. A backup can be either a physical backup or a logical backup.
作為一個備份管理員，你主要的工作是對數據保護的備份進行制定和監控，拷貝數據庫的備份以便你可以用它來重構數據.備份可以是物理備份或者是邏輯備份的其中一種
Physical backups are copies of the physical files used in storing and recovering a
database. These files include data files, control files, and archived redo logs.
物理備份副本的物理文件用于存儲和恢復數據庫，這些文件包含了數據文件,控制文件和歸檔重做日志
Ultimately, every physical backup is a copy of files that store database information to another location, whether on disk or on offline storage media such as tape.
最后，每一個存儲數據庫信息的副本文件放在另一個位置,像在磁盤或者是離線的磁帶設備中
Logical backups contain logical data such as tables and stored procedures. You can use Oracle Data Pump to export logical data to binary files, which you can later import into the database. The Data Pump command-line clients expdp and impdp use the DBMS_DATAPUMP and DBMS_METADATA PL/SQL packages.
邏輯備份包含了像表和存儲過程的邏輯數據.你可以使用Oracle數據泵的方式導出邏輯數據到二級制文件中，你可以在稍后導入到數據庫.數據庫泵的客戶端指令使用PL/SQL包里的 DBMS_DATAPUMP和 DBMS_METADATA中的expdp和impdp
Physical backups are the foundation of any sound backup and recovery strategy.
Logical backups are a useful supplement to physical backups in many circumstances but are not sufficient protection against data loss without physical backups.
物理備份是在所有備份和恢復策略之中最為可靠的基礎.在許多情況下，邏輯備份是物理備份的有用補充，但沒有物理備份對數據丟失的保護是不足夠的。
Unless otherwise specified, the term backup as used in the backup and recovery
documentation refers to a physical backup. Backing up a database is the act of making a physical backup. The focus in the backup and recovery documentation set is almost exclusively on physical backups.
除非另有規定,備份和恢復文檔中使用的術語備份指的是物理備份.備份數據庫是進行物理備份的行為。備份和恢復文檔集中的焦點幾乎完全集中在物理備份上。
While several problems can halt the normal operation of an Oracle Database or affect database I/O operations, only the following typically require DBA intervention and data recovery: media failure, user errors, and application errors. Other failures may require DBA intervention without causing data loss or requiring recovery from
backup. For example, you may need to restart the database after an instance failure or allocate more disk space after statement failure because of a full data file.
雖然一些問題可以使一個Oracle數據庫正常運行停止或影響數據庫的I/O操作，只有在以下情況需要DBA干預和數據恢復：介質故障、用戶錯誤、應用程序錯誤。其他故障可能需要DBA干預在沒有造成數據丟失或要求從備份中恢復。例如，您可能需要重啟數據庫在實例失敗后或者由于完整的數據文件在語句失敗后需要分配更多磁盤空間。
Media Failures
A media failure is a physical problem with a disk that causes a failure of a read from
or write to a disk file that is required to run the database. Any database file can be
vulnerable to a media failure. The appropriate recovery technique following a media
failure depends on the files affected and the types of backup available.
介質故障是一個磁盤的物理問題，它會導致讀取或寫入到需要運行數據庫的磁盤文件失敗。任何數據庫文件都容易受到介質故障的影響。介質故障后的適當的恢復技術取決于受影響的文件和可用的備份類型。
One particularly important aspect of backup and recovery is developing a disaster
recovery strategy to protect against catastrophic data loss, for example, the loss of an entire database host.
備份和恢復的一個特別重要的方面是開發一個災難恢復策略，以防止災難性的數據丟失，例如，整個數據庫主機的損失。
User Errors
User errors occur when, either due to an error in application logic or a manual
mistake, data in a database is changed or deleted incorrectly. User errors are estimated to be the greatest single cause of database downtime.
用戶錯誤發生時，無論是由于應用程序邏輯錯誤或手冊錯誤，數據庫中的數據已經被更改或不正確的刪除。用戶錯誤估計是單一數據庫停機時間最大原因。
Data loss due to user error can be either localized or widespread. An example of
localized damage is deleting the wrong person from the employees table. This type of damage requires surgical detection and repair. An example of widespread damage is a batch job that deletes the company orders for the current month. In this case, drastic action is required to avoid a extensive database downtime.
由于用戶錯誤的數據丟失可以是局部或廣泛。局部損害的一個例子是從雇員表中刪除錯誤的人。這種類型的損傷需要外科探查和修復。一個大范圍損壞的例子是一組作業，刪除當前月份的公司訂單。在這種情況下，需要迅速的采取行動避免大量的數據庫停機時間。
While user training and careful management of privileges can prevent most user
errors, your backup strategy determines how gracefully you recover the lost data
when user error does cause data loss.
雖然用戶培訓和有效的管理權限可以防止大多數用戶錯誤，您的備份策略決定了在用戶錯誤造成數據丟失時如何優雅地恢復丟失的數據。
Application Errors
Sometimes a software malfunction can corrupt data blocks. In a physical corruption,
which is also called a media corruption, the database does not recognize the block at all: the checksum is invalid, the block contains all zeros, or the header and footer of the block do not match. If the corruption is not extensive, then you can often repair it easily with block media recovery.
有時軟件故障會損壞數據塊。在一個物理損壞，也就是所謂的介質損壞，數據庫根本不識別所有的塊：校驗無效，塊包含所有的零點，或塊的頭和尾不匹配。如果損壞不大量，那么你可以經常輕松的使用塊介質恢復。
About Data Archival
Data archival is related to data protection, but serves a different purpose. For example,you may need to preserve a copy of a database as it existed at the end of a business quarter. This backup is not part of the disaster recovery strategy. The media to which these backups are written are often unavailable after the backup is complete. You may send the tape into fire storage or ship a portable hard drive to a testing facility. RMAN provides a convenient way to create a backup and exempt it from your backup retention policy. This type of backup is known as an archival backup.
數據存檔與數據保護有關，但服務的目的不同。例如，您可能需要保存一個數據庫的副本，因為它在業務季度結束時存在。此備份不是災難恢復策略的一部分。備份完成后，寫入這些備份的媒體通常不可用。您可以將磁帶發送到消防倉庫，或將便攜式硬盤傳送到測試設備。RMAN可以方便地創建一個備份，免除您的備份策略。這種類型的備份被稱為歸檔備份。
About Data Transfer
In some situations you may need to take a backup of a database or database
component and move it to another location. For example, you can use Recovery
Manager (RMAN) to create a database copy, create a tablespace copy that can be
imported into another database, or move an entire database from one platform to
another. These tasks are not strictly speaking part of a backup and recovery strategy,but they do require the use of database backups, and so may be included in the duties of a backup administrator.
在某些情況下，您可能需要備份數據庫或數據庫組件并將其移動到另一位置。例如，你可以使用恢復管理器（RMAN）創建一個數據庫副本，創建一個可以導入到另一個數據庫表空間副本，或整個數據庫從一個平臺移動到另一個。這些任務不是嚴格地說是備份和恢復策略的一部分，但它們確實需要使用數據庫備份，因此可以包含在備份管理員的職責中。
Oracle Backup and Recovery Solutions
When implementing a backup and recovery strategy, you have the following solutions available:
在貫徹數據備份和恢復策略中，你有以下幾種可用的解決方案
? Recovery Manager (RMAN)
Recovery Manager is fully integrated with the Oracle Database to perform a range
of backup and recovery activities, including maintaining an RMAN repository of
historical data about backups. You can access RMAN through the command line or
through Oracle Enterprise Manager.
恢復管理器是完全集成的Oracle數據庫執行范圍備份和恢復活動,包括維護一個RMAN庫歷史數據備份。你可以通過命令行訪問RMAN活通過 通過OEM
? Oracle Enterprise Manager Cloud Control
Oracle Enterprise Manager Cloud Control (Cloud Control) provides a graphical
front end and scheduling facilities for RMAN. You enter job parameters, specify a
job schedule, and Cloud Control runs RMAN to conduct the backup and recovery
operations.
OEM云管理提供了前端圖形和RMAN調度工具,你輸入一個任務參數,指定任務跳讀，云控制臺運行RMAN進行備份和恢復操作
? Zero Data Loss Recovery Appliance (Recovery Appliance)
Recovery Appliance is a cloud-scale Engineered System that provides data
protection for all Oracle Databases in the enterprise. Integrated with RMAN and
Cloud Control, the Recovery Appliance provides a single repository for backups of
multiple databases as described in “About Zero Data Loss Recovery Appliance”.
恢復設備是一個云規模的工程系統，提供數據企業中所有Oracle數據庫的保護。RMAN和云控制集成，恢復設備提供了一個用于多個數據庫備份的倉庫作為在“零數據丟失恢復設備”的描述。
? User-managed backup and recovery
In this solution, you perform backup and recovery with a mixture of host operating
system commands and SQL*Plus recovery commands.You are responsible for
determining all aspects of when and how backups and recovery are done.
在這個解決方案中，您執行備份和恢復使用宿主操作系統命令和SQL * Plus恢復命令。你負責確定各方面何時以及如何備份和恢復。
These solutions are supported by Oracle and are fully documented, but RMAN is the preferred solution for database backup and recovery. RMAN provides a common interface for backup tasks across different host operating systems, and offers several backup techniques not available through user-managed methods.
這些解決方案通過Oracle的支持和豐富的文檔支持，但是RMAN數據庫備份和恢復是首選解決方案。RMAN提供的備份任務在不同的主機操作系統的一個通用的接口，并在無法通過用戶管理的方法上提供了多種備份技術。
Most of this manual focuses on RMAN-based backup and recovery. The most
noteworthy are the following:
基于RMAN備份和恢復是手冊重點。最值得注意的是以下
? Incremental backups
An incremental backup stores only blocks changed since a previous backup. Thus,
they provide more compact backups and faster recovery, thereby reducing the
need to apply redo during data file media recovery. If you enable block change
tracking, then you can improve performance by avoiding full scans of every input
data file. You use the BACKUP INCREMENTAL command to perform incremental
backups.
增量備份只存儲塊一次備份后改變。因此，他們提供了更緊湊的備份和更快的恢復，從而減少了需要應用重做數據文件介質恢復過程。如果你啟用塊更改跟蹤，然后你可以通過避免每個輸入數據文件的完全掃描提高性能。你使用增量備份命令執行增量備份。
? Block media recovery
You can repair a data file with only a small number of corrupt data blocks without
taking it offline or restoring it from backup. You use the RECOVER BLOCK
command to perform block media recovery.
您可以僅使用少量已損壞的數據塊修復數據文件使其脫機或從備份還原。 您使用RECOVER BLOCK命令執行塊介質恢復。
? Binary compression
A binary compression mechanism integrated into Oracle Database reduces the size
of backups.
集成到Oracle數據庫中的二進制壓縮機制減少了備份的大小。
? Encrypted backups
RMAN uses backup encryption capabilities integrated into Oracle Database to
store backup sets in an encrypted format. To create encrypted backups on disk, the
database must use the Advanced Security Option. To create encrypted backups
directly on tape, RMAN must use the Oracle Secure Backup SBT interface, but does not require the Advanced Security Option.
RMAN使用集成到Oracle數據庫中的備份加密功能以加密格式存儲備份集。 要在磁盤上創建加密備份，數據庫必須使用高級安全選項。 創建加密備份直接在磁帶上，RMAN必須使用Oracle Secure Backup SBT接口，但不需要高級安全選項。
? Automated database duplication
自動數據復制
Easily create a copy of your database, supporting various storage configurations,
including direct duplication between ASM databases.
輕松創建數據庫的副本，支持各種存儲配置，包括ASM數據庫之間的直接復制。
? Cross-platform data conversion
跨平臺數據轉換
User-managed backup and recovery techniques are covered in chapters Making User-Managed Database Backups through Performing User-Managed Recovery: Advanced Scenarios.
用戶管理的備份和恢復技術覆蓋在使用戶管理通過執行用戶管理恢復的數據庫備份的章節：高級方案的章節中介紹。
Whether you use RMAN or user-managed methods, you can supplement physical
backups with logical backups of schema objects made with Data Pump Export utility.
無論您使用RMAN還是用戶管理的方法，都可以補充物理備份與使用數據泵導出實用程序進行的模式對象的邏輯備份。
You can later use Data Pump Import to re-create data after restore and recovery.
Logical backups are mostly beyond the scope of the backup and recovery
documentation.
你可以稍后在還原和恢復后重新創建數據時使用數據泵導入。邏輯備份大多超出了備份和恢復文檔的范圍
The following table summarizes the features of the different backup techniques.
一下表格總結了不同備份技術的功能
