DiskMaster vs Prefail

DiskMaster is a free desktop application for monitoring drive health on Windows, Linux, and macOS. It reads SMART attributes, self-tests, and test logs, then calculates a health score out of 100 and shows which attributes account for deductions; performance has a separate score. It stores readings in SQLite and charts changes, with alerts for shifts such as increasing drive counters. A read-only surface scan times blocks, rereads unreadable sectors for confirmation, and maps them to sectors. DiskMaster can identify files associated with those sectors and try to rescue copies while skipping unreadable bytes. Optional repair tools include sector and filesystem repair, zero-fill, and sanitizing bad sectors the filesystem marks as free. Alerts can go to Slack, Discord, ntfy, email, desktop notifications, commands, or JSON webhooks. Its CLI exports text, HTML, JSON, and CSV reports. SATA and USB monitoring needs no third-party tools; NVMe health logs and macOS use optional smartmontools. Raw SMART access requires administrator or sudo privileges.

Prefail monitors disk S.M.A.R.T. health across server fleets and sends warnings about problems and possible next steps. Its SENTINEL system weighs more than 25 S.M.A.R.T. attributes to assign each disk a risk score from 0 to 100, with history views showing seven-day changes and whether signals are stable or rising. Alerts include severity, an explanation, and a recommended action, and can be acknowledged, muted, or dismissed in batches. Supported RAID setups include MegaRAID 9260/9361/9460, Adaptec SmartRAID, and Linux mdadm, with visibility into disks behind controllers. Prefail offers Telegram alerts and a Telegram Mini App dashboard, with email as a fallback, plus a weekly PDF fleet report. Its Linux agent is a Bash script that runs smartctl and transmits S.M.A.R.T. output. Prefail says it sends data over TLS and stores it on a dedicated European server. The free tier covers up to two servers; paid plans start at $9/mo. The maker warns that S.M.A.R.T. monitoring cannot catch sudden failures and does not replace backups.