Beijing Tianchuang Jiacheng (channel dealer)

Server R730 dual machine hot standby scheme

one Dual computer Hot standby It refers to the hot standby (or high availability) based on two servers in the high availability system. Because the high availability of two servers is widely used in China, it is called dual hot standby. According to the switching mode in work, dual high availability can be divided into: active standby mode (Active Standby mode) and dual host Mode (Active Active mode). The active standby mode means that one server is in the active state (Active state) of a certain service, and the other server is in the standby state (Standby state) of the service. The dual host mode refers to the active standby and standby active state of two different services on two servers. More mature Dual computer hot standby software Usually Hard disk data Interception technology, usually called image The software is the Mirror software. This technology is very mature at present, and the interception methods are different.

two The shared storage mode is mainly provided by the disk array Data integrity And continuity. The user data is usually placed on the disk array Downtime After that, the standby machine continues to obtain the original data from the disk array. As shown in the figure below, this method is often called disk by industry insiders because it uses a storage device Single point of failure 。 But generally speaking, the storage security is high. Therefore, if the storage device failure is ignored, this mode is also the most popular hot standby mode in the industry.

Full redundancy mode

one whole redundancy The way is double computers storage , based on the tradition of single storage hot standby The storage does exist Single point of failure To achieve storage redundancy, Storage highly available It has been accepted by more and more users. We can see from our understanding that, hot standby It was originally a solution to solve the planned and unplanned downtime of servers, but we cannot achieve the server downtime caused by the planned and unplanned downtime of storage hot standby The only device that stores data in the hot standby The system crashed completely.

With the progress of science and technology, cloud storage ， cloud computing The development of storage hot standby has entered a mature and rapid development stage, hot standby With the progress of technology, it has entered into the full range without single point of failure redundancy hot standby Mode. As shown in the figure:

This method is characterized by:

1、 storage Data replication between storage Copy between.

2. The replication between two stores is completely real-time, without any time delay.

3. The switching time between the active and standby storage is less than 500ms to ensure that there is no delay in system storage.

4. Hard disk Drive letter The partition is not changed due to the switch between primary and standby storage.

5. Server switching does not affect the initialization, incremental synchronization and data replication between stores.

6. Planned downtime of a storage device does not affect the entire server Dual machine hot standby system Work.

7. Use between storage devices Deduplication Technology to complete incremental synchronization.

8. True 7X24 hours or switched full redundancy Programme.