Disaster Recovery System
For servers, systems, or networks that require high availability and stability, system designers usually design failover functions. At the server level, automatic failover typically connects two servers with a heartbeat line. The standby server will not be enabled as long as the pulse or heartbeat between the primary server and the standby server is not interrupted. In order to hot switch and prevent service disruptions, a third server may also be running standby components. When the primary "heartbeat" alarm is detected, the standby server takes over the service. Some systems have the ability to send failover notifications. Some systems are deliberately designed not to be fully automatic failover, but to require administrator intervention. This "manual automatic failover" configuration, when the administrator confirms the failover, the whole process will be completed automatically.