A server administrator is deploying a new, mission-critical server that features dual, hot-swappable power supplies. The server rack is equipped with two separate Power Distribution Units (PDUs), labeled A and B. To provide the highest level of power fault tolerance for the server, which of the following connection strategies should be implemented?
Connect one server power supply to PDU A and the other to PDU B. Each PDU should be connected to an independent Uninterruptible Power Supply (UPS) and a separate electrical circuit.
Connect both server power supplies to different outlets on PDU A, which is connected to a single, high-capacity UPS.
Connect one server power supply to PDU A on a UPS-protected circuit and the other server power supply directly to a separate, non-UPS wall outlet.
Connect one server power supply to PDU A and the other to PDU B, with both PDUs connected to the same UPS.
The correct approach is to create two fully independent power paths, often referred to as an A/B power configuration. By connecting each of the server's power supplies to separate Power Distribution Units (PDUs), the configuration protects against a PDU failure. Ensuring each PDU is fed by an independent Uninterruptible Power Supply (UPS) on a separate electrical circuit protects against a UPS failure or a circuit breaker trip. This design eliminates any single point of failure in the power delivery system from the utility to the server. Connecting both power supplies to the same PDU or the same UPS creates a single point of failure, negating the benefit of having dual power supplies. Connecting one power supply to a non-UPS outlet removes the critical battery backup protection from that power path, exposing the server to data loss or downtime during a power outage.