Backup Modes
The device provides the HSB solution in active/standby mode.
Active/Standby Mode (Using VRRP Hot Standby)
As shown in Figure 5-1, RouterA and RouterB form a VRRP group. RouterA is the master device and RouterB is the backup device. When RouterA is working normally, it processes all services and transmits session information to RouterB through the HSB channel. RouterB does not process services and only backs up session information.
When RouterA fails, RouterB starts to process services, as shown in Figure 5-2. Because session information is backed up on RouterB, new sessions can be set up without interrupting the current session. This improves network reliability.
When the original master device (RouterA) recovers, it becomes the master in preemption mode. In non-preemption mode, RouterA retains in Backup state.