Hardware
What is actually on the shelf. Updated when something changes, which is less often than I would like to admit.
| Part | Details | Since |
|---|---|---|
| Main box | Used mini PC, 4 cores, 16 GB RAM | 2024 |
| System disk | 500 GB NVMe | 2024 |
| Bulk disk | 4 TB 2.5" HDD in a USB enclosure | 2025 |
| Backup disk | 4 TB HDD, separate enclosure, separate power strip | 2025 |
| UPS | Small line-interactive unit, about 25 minutes at idle | 2025 |
| Balcony node | ESP32 + BME280 + rain gauge | 2025 |
Power
The whole shelf draws 9–11 W at idle with the bulk disk asleep, and around 24 W during the nightly backup. Over a year that is a little under 100 kWh.
Software, briefly
Debian stable, unattended security updates, containers for anything that is not part of the base system. Each service keeps its data in one directory so that backing it up and moving it are the same operation.