Dual-device backup is a feature that ensures service traffic continuity in scenarios in which a master/backup status negotiation protocol (for example, VRRP or E-Trunk) is deployed. Dual-device backup enables the master device to back up service control data to the backup device in real time. When the master device or the link directly connected to the master device fails, service traffic quickly switches to the backup device. When the master device or the link directly connected to the master device recovers, service traffic switches back to the master device. Therefore, dual-device backup improves service and network reliability.
In traditional service scenarios, all users use a single device to access a network. Once the device or the link directly connected to the device fails, all user services are interrupted, and the service recovery time is uncertain. To resolve this issue, deploy dual-device backup to enable the master device to back up service control data to the backup device in real time.
Improved service and network reliability. If a network goes faulty, the slave device can quickly take over user services, so that users can use network resources continuously without realizing the network failure.