Which statement is true regarding failover.

Hardware failover is often considered a primary failover method and is usually enabled or considered integral when a serial cable is connected.

BIG-IP high-availability pairs commonly utilize both hardware failover, which relies on a direct serial connection for a low-latency heartbeat, and network failover, which sends heartbeats over network interfaces. These two methods can be configured and operate simultaneously, providing a robust, multi-layered approach to detecting peer availability and ensuring a timely and accurate failover decision.

If the hardware failover cable is disconnected, the system detecting the loss of voltage would typically assume its peer has failed, but it would not automatically result in both devices always becoming active without other failover mechanisms confirming the peer's state.

Hardware failover primarily detects the presence of voltage for a simple heartbeat signal across the serial cable, not traffic, which is handled by network failover.