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Data Backup/recovery scenario
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principles of data backupThe data is backed up to ensure consistency and integrity of the data, eliminating the worries of users and operators of the system. Different application environments require different solutions to adapt, in general, a perfect backup system, you need to meet the following principles:
StabilityThe primary role of a backup product is to provide a method of data protection for the system, and the stability and reliability of the product itself becomes one of the most important aspects. First, the backup software must be compatible with operating system 100%, and secondly, the data can be recovered quickly and efficiently when an accident occurs.
ComprehensiveIn a complex computer network environment, may include a variety of operating platforms, such as the various manufacturers of UNIX, NetWare, Windows NT, VMS, etc., and installed a variety of application systems, such as ERP, database, groupware systems. Select backup software to support a variety of operating systems, databases, and typical applications.
AutomateMany systems, due to their nature of work, have certain limitations on when to back up and how long to back up. The system is light in time of work and is suitable for backup. However, this will increase the burden on the system administrator, due to mental state and other reasons, but also to the security of backup potential hidden dangers. Therefore, the backup scheme should be able to provide regular automatic backup, and the use of tape libraries and other technologies for automatic belt replacement. In the automatic backup process, also have logging function, and in the event of an exception automatically alarm.
High PerformanceWith the continuous development of the business, more and more data, update faster, in the rest time too late to back up so much content, in the working time backup will affect the system performance. This requires that when designing a backup, try to consider ways to improve the speed of data backup and take advantage of multiple tape drives in parallel operations.
Simple OperationData backup is applied to different fields, and the operators who perform data backup are at different levels. This requires an intuitive, simple operation of the graphical user interface, shorten the learning time of the operator, reduce the working pressure of the operator, so that backup work can be easily set up and completed.
Real-time performanceSome of the key tasks are to run for 24 hours without downtime, and some files may still be open during backup. Then, when backing up, take steps to view the file size and transaction tracking in real time to ensure that all files in the system are backed up correctly.
Disaster tolerance ConsiderationsCopy a tape from a tape library to a location away from the data center to prevent unpredictable disaster in the data center.
2Backup System CompositionWhether a safe and effective backup depends on the following three factors y the quality and performance of the tape drive tape drive that performs the backup is critical throughout the backup process and is critical for high-speed, high-quality backups. Y storage Backup Data media is the load of data, its quality must be guaranteed, the use of quality is not pass the media is undoubtedly to take their own data adventure. The software operating system that controls backup typically includes basic functionality, but for better backup, it is best to use specialized backup software. Excellent backup software, including accelerated backup, automatic operation, disaster recovery and other special features, for safe and effective data backup is very important.3Backup StrategyIn addition to the above principles, a good backup/recovery system, in addition to equipped with good hardware and software, the need for a good backup strategy and management planning to ensure that. For a complex system, a specific backup strategy must be developed according to the types of applications and services. But generally speaking, a good backup strategy is composed of the following content:3.1selection of backup typesThere are three main types of backup: Y full backup: Each backup defines all the data, the advantage is to recover quickly, the disadvantage is that the large amount of backup data, data can do a full backup for a long time y incremental backup: Backs up all data that has been updated since the last backup, with the advantage of each backup Small amount of data, the disadvantage is that the recovery requires full backup and multiple incremental backup y differential backup: Backs up all the data that has been updated since the last full backup, with the pros and cons between the two when choosing a backup type, the general rule is: Y for the operating system and application code, you can Do a full backup when the system updates or installs new software y for some of the daily data updates are large, but the overall data volume is not a very large key application data, you can schedule a full backup every day when the user's use is small for daily updates relative to the overall amount of data is small, and the overall amount of data is very Large critical application data that can be scheduled for a full backup every one months or a week, and on this basis, incremental backups are made every other short time interval3.2Backup Window SelectionThe backup window, which is the interval between each backup, depends largely on the amount of data that is lost, the amount of data that is backed up, and the speed of the backup, each time the backup interval is available. Theoretically, the shorter the backup interval the better, but each backup will always take a certain amount of time, and the backup always more or less affect the system's normal processing performance. Thus, for some critical data, you can define the backup window size in advance, and then calculate the required backup speed based on the amount of backup data, and if the backup speed does not meet the requirements, consider using a faster library or adding drive data on the tape library. Its calculation process is: l Determine the amount of backup data and data compression ratio l calculate the backup speed of a single drive based on the controller type L determine the required Backup window L calculate the required backup time for a single drive l determine the required drive Number of Actuators3.3Determine media save timeWith a large amount of storage media to be used during the backup process, the length of retention time of the backup media determines the quality of the required acquisition and maintenance. The current backup strategy is based on multiple tape rotations, which means that the media that holds obsolete data can be reused, and the frequency of rotation can be determined by the backup type and the backup window.3.4calculate the number of tape media requiredThe number of media required to back up the system can be determined according to the following process: L Determine the media capacity
