Disaster recovery system refers to the establishment of two or more sets of IT systems with the same function in distant places, which can perform health monitoring and function switching between each other. When a system stops due to an accident (such as fire, earthquake, etc.) When working, the entire application system can be switched to another place, so that the system functions can continue to work normally. Disaster recovery technology is an integral part of the system's high availability technology. The disaster recovery system puts more emphasis on dealing with the impact of the external environment on the system, especially the impact of catastrophic events on the entire IT node, and provides node-level system recovery functions.
Disaster tolerance classification
According to the degree of protection of the system, the disaster recovery system can be divided into: data disaster recovery and application disaster recovery
Described as follows:
Data disaster tolerance refers to the establishment of a remote data system, which is a real-time copy of local key application data.
Application disaster recovery is based on data disaster recovery, and establishes a complete set of backup application systems (which can be mutual backups) equivalent to local production systems in remote locations. In the event of a disaster, the remote system quickly takes over business operations. Data disaster tolerance is a guarantee against disasters, and application disaster tolerance is the goal of disaster recovery system construction.
Data disaster recovery
The so-called data disaster tolerance refers to the establishment of a remote data system, which is a usable copy of local key application data. In the event of a disaster in the local data and the entire application system, the system at least keeps a copy of the critical business data available in different locations. This data can be completely real-time copied from the local production data, or it can be slightly behind the local data, but it must be available. The main technology used is data backup and data replication technology.
Data disaster recovery technology, also known as off-site data replication technology, can be divided into synchronous transmission mode and asynchronous asynchronous transmission mode according to the technical method of its implementation (each manufacturer may have different technical terms), in addition, there are Such as "semi-synchronous". The semi-synchronous transmission mode is basically the same as the synchronous transmission mode, except that when the proportion of Read accounts for I / O is relatively large, the I / O speed can be slightly increased compared to the synchronous transmission mode. According to the distance of disaster recovery, data disaster recovery can be divided into remote data disaster recovery and short-range data disaster recovery. In the following, we will mainly discuss data disaster recovery in terms of synchronous transmission mode and asynchronous asynchronous transmission mode, which will also involve the concepts of remote disaster recovery and short-range disaster recovery, and make corresponding analysis.
Application of disaster recovery methods
The so-called application disaster recovery is to build a complete set of backup application systems (may be mutual backups) in a remote place on the basis of data disaster recovery. Building such a system is relatively complicated, not only requires a copy of the available data, but also resources including network, host, application, and even IP, as well as good coordination between the resources. The main technologies include load balancing and cluster technology. Data disaster recovery is the technology of application disaster recovery, and application disaster recovery is the goal of data disaster recovery.
When choosing the construction of a disaster recovery system, a multi-level wide area network failover mechanism must also be established. Local high-availability system means that when multiple servers are running one or more applications, it should be ensured that when any server fails, the applications it runs cannot be interrupted, and applications and systems should be able to quickly switch to other servers. That is, the local system cluster and hot backup.
In a remote disaster recovery system, to achieve complete application disaster recovery, it should include not only the local system security mechanism, remote data replication mechanism, but also the wide area network range of remote failover capabilities and fault diagnosis capabilities. In other words, once a fault occurs, the system must have a powerful fault diagnosis and switching strategy formulation mechanism to ensure rapid response and rapid business takeover. In fact, the high availability capability of the wide area network and the high availability capability of the local system should form a whole, implement a multi-level failover and recovery mechanism, and ensure the reliability and safety of the system in various ranges.
The cluster system is built on the basis of redundant general availability systems and runs high-reliability software. The high-reliability software is used to automatically detect the operating status of the system. In the event of a server failure, it automatically transfers the set service to another server. When the service provided by the running server is not available, the backup server automatically takes over the work of the running server without restarting the system, and when the running server returns to normal, the service is switched to the running service in an automatic or manual manner according to the user's settings . In addition to taking over its services when the running server fails, the backup server can also execute other applications. Therefore, a fully equipped host can be used as a running server of a service and a backup server of another service, that is, the two servers back up each other. A host can run multiple services, and can also serve as a backup server for multiple services.
Data disaster recovery system, for IT, is an environment for computer information systems that can cope with various disasters. When a computer system is subjected to irresistible natural disasters such as fires, floods, earthquakes, wars, and other man-made disasters such as computer crime, computer viruses, power failure, network / communication failure, hardware / software errors, and human operation errors, the disaster recovery system It will ensure the security of user data (data disaster recovery), and even a more complete disaster recovery system can provide uninterrupted application services (application disaster recovery). It can be said that the disaster recovery system is the highest level of data storage backup.
Two technical indicators to measure disaster recovery backup
RPO (Recovery Point ObjecTIve): data recovery point objective, mainly refers to the amount of data loss that the business system can tolerate.
RTO (Recovery TIme ObjecTIve): the recovery time objective, mainly refers to the longest time that the business can tolerate the stop of service, that is, the shortest time period required from the disaster to the business system recovery service function.
RPO is for data loss, while RTO is for service loss, and the two are not necessarily related. The determination of RTO and RPO must be based on different business needs after risk analysis and business impact analysis. For the same business of different enterprises, the needs of RTO and RPO will also be different.
Qunsuo is a professional manufacturer of Barcode Scanner. We provide 1D Barcode Scanner and Qr Code Scanner , help customers from various industries. All of our barcode scanner support connecting with Android IOS via bluetooth. Furthermore, Our barcode scanner also support connecting with PC via 2.4G wireless module. Qunsuo provide portable scanner, Finger Barcode Scanner and Handheld Barcode Scanner. And our QS-S03 is equipped with Zebra scanner engine. If any interests, please feel free to send inquiry to us for more information.
Barcode Scanner
2D Barcode Scanner,Free Barcode Scanner,Finger Barcode Scanner,Barcode Scanner Android
Shenzhen Qunsuo Technology Co., Ltd , https://www.qsprinter.com