F5 BIG-IP LTM Specialist: Maintain and Troubleshoot — Question 128

A high-availability (HA) pair configuration uses only the hardwire serial cable connection to determine device state. A power outage occurs to the PDU powering the active unit. The standby unit takes over the active role as expected.
How is the peer unit able to determine the active unit is unavailable?

Answer options

• A. voltage loss on serial cable
• B. no data stream received on serial port
• C. no response on management interface
• D. no heartbeat packets received on self IPs

Correct answer: A

Explanation

The correct answer is A because the loss of voltage on the serial cable indicates that the active unit is not powered and thus unavailable. Options B, C, and D do not apply in this specific scenario since the power loss would directly affect the voltage rather than the data stream, management interface, or heartbeat packets.