UPS - Uninterruptible Power Supply

The NetYeti’s Guide to Not Losing Data: UPS

In the home lab, power is your most critical dependency. A UPS (Uninterruptible Power Supply) isn’t just about keeping the lights on; it’s about a “Graceful Shutdown.”

Why You Need One

• Data Integrity: Sudden power loss during ZFS writes or database transactions is the fastest way to a “manageable mess.”
• Hardware Longevity: Brownouts and surges kill power supplies and motherboards.
• Service Continuity: Keep your router and core services up during short blips.

PACE Plan for Power

• P (Primary): Utility Power (Grid).
• A (Alternate): UPS Battery Backup.
• C (Contingency): Automatic Shutdown Script (triggered at 20% battery).
• E (Emergency): Manual intervention / Generator.

Software Stack

To manage your UPS, you’ll typically use:

1. NUT (Network UPS Tools): The industry standard for managing multiple devices from one UPS.
2. APCUPSD: Specifically for APC brand units, very reliable and simple to configure.

Knowledge Check:

• Is your UPS battery tested annually?
• Do your servers actually shut down when the signal is sent? (Test it!)

TIP

Always over-provision your UPS by at least 20% of your total lab draw to account for battery degradation over time.