CompTIA Server+ (SK0-005)TroubleshootingEasy
A server is configured with a redundant power supply unit (PSU) setup. The administrator receives an alert that one of the PSUs has failed. Upon inspection, the indicator light on PSU1 is amber, while PSU2's light is green. The server remains operational without any performance issues. What is the immediate impact of this failure?
- AThe server is now drawing power from an auxiliary battery.
- BThe server will immediately shut down.
- CThe server's performance will be significantly degraded.
- DThe server has lost its power redundancy.
Show answer & explanationAnswer & explanation
Correct answer: D. The server has lost its power redundancy.
A redundant PSU configuration means the server can operate with one PSU failing, as the other takes over the full load. The immediate impact of one PSU failure is the loss of this redundancy. The server is still operational but now has a single point of failure for power.
Why the other options are wrong
- A. Redundant PSUs are independent of auxiliary batteries (UPS systems) and do not switch to them automatically upon single PSU failure.
- B. Redundant PSUs are designed to prevent immediate shutdown upon a single PSU failure.
- C. The failure of one PSU in a redundant setup typically does not degrade server performance, as the remaining PSU is designed to handle the full load.
Redundant Power Supply Failure
In a server with redundant power supplies, the failure of one PSU means the system loses its fault tolerance for power, operating on a single point of failure until the failed unit is replaced.
- Server remains operational with one failed PSU.
- Loss of redundancy is the immediate consequence.
- Replacement is critical to restore fault tolerance.
Memory trick: Two PSUs are nice and dandy, but one goes out, redundancy's scanty.