A new rack of servers has been installed in a datacenter. A server administrator needs to ensure fault tolerance and redundancy wherever possible. Which of the following would ensure the MOST uptime…

Connecting rack PDUs to separate power circuits ensures that a tripped breaker or failed circuit does not take down all equipment in the rack simultaneously, providing circuit-level redundancy.

Connecting servers that have multiple power supply units to separate power sources means each PSU draws from a different feed, so the loss of any single PDU, circuit, or source does not interrupt the server - fulfilling redundancy at the hardware level.

Periodically testing UPS batteries is a maintenance best practice but does not provide redundancy - a failed UPS still represents a single point of failure for everything connected to it.

Connecting redundant PSUs to the same PDU defeats the purpose of having multiple power supplies because a single PDU failure would drop both feeds simultaneously.

Connecting all PDUs to a single UPS creates one point of failure at the UPS device, removing true redundancy even if the PDUs are on separate circuits.

Connecting multiple PSUs to the same higher-amp circuits still ties both power feeds to one circuit, so a circuit fault removes all power to the server.