Before, when developing active/active mode, network managers needed to reserve 20-25% of system resources in anticipation of failover events. This restricted both network performance and capacity. Furthermore, network managers had to clearly understand the intricacies of "dynamic routing" and "asymmetric flow", which are too complex for the average individual.
Zyxel Device HA Pro adopts active/passive mode, a simple and reliable approach for those who do not wish to unravel complicated configuration protocols. Passive device reserves capacity to take over the network instantly and maintain normal operations.
The HA Pro provides an active/passive device exchange heartbeat through a dedicated port, which can be assigned to the last port on Zyxel USG series products. An Ethernet cable can be used to connect the dedicated port of both active and passive devices. Passive device not only helps synchronize connection information from active device, but also backs up the configuration file to ensure the device settings are always safe. In addition, passive device will disable all ports to avoid other conflicts. With the improvements to the HA Pro, synchronization data contains more traffic details, allowing passive device to minimize downtime.
Device HA Pro delivers a Instant Handover that the user is not even aware when it happens. Passive device will be triggered to take over the network and enforce the same policies to recover normal operations within just five (5) seconds, when one of the following situations occurs:
Once active device (HA1) is dead, it releases its role. After recovering from a failure, HA1 will play the passive role to back up the network and stand by for on-going active device (HA2). Devices only switch roles when failover occurs to limit interfere caused by system change.