【 Weak current college 】 technical basis on standby

Hot standby in long-term use has a lot of users have summarized many of the skills experience, there are some concepts are more we need to know about, the following is the details of hot standby technology need to understand the concept.

Hot standby technology needs to be pointed out a few concepts:

1. standby technology works

Fault isolation, simple, high-availability (hot) is a kind of the point of failure to protect the transfer of business continuity. Its business recovery is not in the original server, which is in the standby server. Hot does not have the repair the failed server's features, but only fault isolation.

2. standby mode technical Active-Active

Active-Active way refers to the business rather than the server status, if the same application is not complete Active-Active manner. For example, hot two servers is sqlserver database, it is referring to a different database instance. The same database instance is not possible in hot this level Active-Active manner. Simple Active-Active is two way run to Active-Standby on both servers.

3. Standby failure detection

Fault detection is hot standby technology tasks, different double machine detection point number determines the hot standby software in functionality and performance of good and bad, not all software will have the same detection capabilities to PlusWell camputer technology software, for example, it provides a full system detection capability, that is, there are system-level detection, application-level, network level three. System-level testing through hot standby technology software provides a system for the detection of cardiac function, the application level provides the user applications, databases, and other detection feature, the network level detection provides network connection detection and optional on network path detection capabilities, so called full fault detection capabilities.

4, server resources

Hot standby resource refers to a business operation relies on the smallest of the associated services, different two-machine software provides resources, how many different, of course, you can toggle the resources available, the more software applications, also in hot standby technology in server resources mainly include, switch network IP resource, computer name, disk volume resource, the server process.

5, hot standby switch technology

-Standby switch generally consists of manually switch and failover, which is planned to switch (i.e. people switch) and non-planned switch (failover).

Need we note that not all resources have to switch to PlusWell hot backup software as an example he provides:

(1) local resource monitoring, that is not switching resources.

(2) ordinary resource, that is, you can switch the main machine resources.

(3) quick resources refers to quickly switch resources

In the General case of dual switching time is 1-5 minutes, and quickly switch in time is 3-5 seconds. Users should be according to their needs and operational features to select relevant switching service, from the price-cost point of view, the switching time that costs are also higher.

6. standby technology copy and backup concept is the difference between

Hot Backup refers to: highavailable is highly available, while the backup is a Backup, data backup, this is two different concepts, products are two functions on an entirely different product. Hot backup main guarantees the continuity of the business, realization of methods is the point of failure and backup of the transfer, the primary objective is to prevent data loss, do a test Bay, so backup is data recovery instead of application failover.