Prefail
What it is
Prefail is a Linux and API service for monitoring disk health across server fleets. It reads S.M.A.R.T. data and assigns each disk a 0–100 SENTINEL risk score based on more than 25 attributes. Score history records seven-day changes and labels signals as stable or rising. Alerts include severity, a plain-language explanation, and a recommended action, with controls to acknowledge, mute, or dismiss several alerts together. Prefail supports MegaRAID 9260, 9361, and 9460, Adaptec SmartRAID, and Linux mdadm, including health details for disks behind controllers. Notifications can arrive through Telegram, its Telegram Mini App dashboard, or email. A Monday PDF report summarizes degraded disks, changes, and replacement guidance. The Linux agent is a small Bash script using smartctl and curl, and the maker says it collects only S.M.A.R.T. data. Plans include a free tier for two servers and paid plans from $9/mo.
For and against
For
- SENTINEL scores disks from 0–100
- Tracks seven-day score changes
- Supports specified RAID controllers and mdadm
- Telegram dashboard and email fallback
- Free plan covers up to two servers
Against
- S.M.A.R.T. misses sudden electrical failures
- Not a substitute for backups
- Free plan checks every 30–60 minutes
The verdict
Prefail combines disk-risk scoring, history, controller-aware monitoring, and actionable alerts for fleet operators. Its limits around sudden failures mean it should complement, not replace, backup practices.
Who it suits
Prefail suits operators responsible for monitoring disk health across server fleets, especially Linux environments and supported RAID controllers. It is also intended for teams needing scheduled reports and alert routing through Telegram or email.
Plans and prices
FREE
Up to 2 servers · PULSE 30–60 min · 7-day score history · Email alerts (1 recipient)
Read 8 Oct 2026 · prefail.io
PRO
Up to 20 servers per account · PULSE 5–30 min · 90-day score history · Email alerts (3 recipients)
Read 8 Oct 2026 · prefail.io
BUSINESS
Up to 75 servers per account · PULSE 5–30 min · 180-day score history · Email alerts (5 recipients)
Read 8 Oct 2026 · prefail.io
SCALE
Up to 250 servers per account · PULSE 1–30 min · 365-day score history · Unlimited email recipients
Read 8 Oct 2026 · prefail.io
ENTERPRISE
Unlimited servers · PULSE 1 min · Unlimited score history · Unlimited email recipients
Read 8 Oct 2026 · prefail.io
On the record
- Alerts
- Alerts include severity, a human-readable explanation, and an actionable recommendation, with options to acknowledge, mute, or batch dismiss.prefail.io · read 8 Oct 2026
- Data collection
- The agent collects only S.M.A.R.T. data and does not access files, scan the network, or list processes.prefail.io · read 8 Oct 2026
- Data handling
- The site says data is stored on a dedicated server in Europe and offers GDPR-ready data export and deletion.prefail.io · read 8 Oct 2026
- Deployment
- The Linux agent is an approximately 250-line Bash script that runs smartctl and sends its output with curl.prefail.io · read 8 Oct 2026
- Integrations
- The product provides Telegram alerts and a Telegram Mini App dashboard, with email alerts as a fallback.prefail.io · read 8 Oct 2026
- Intended users
- Prefail describes itself as a specialist tool for monitoring disk health across server fleets.prefail.io · read 8 Oct 2026
- Limits
- Prefail warns that S.M.A.R.T. detects gradual degradation, not sudden failures such as power surges, controller burnout, or electrical damage, and says it is not a substitute for backups.prefail.io · read 8 Oct 2026
- Purpose
- Prefail monitors disk S.M.A.R.T. health and sends alerts about disk problems and recommended actions.prefail.io · read 8 Oct 2026
- RAID support
- It supports MegaRAID 9260/9361/9460, Adaptec SmartRAID, and Linux mdadm, including individual disk health behind controllers.prefail.io · read 8 Oct 2026
- Reports
- Prefail sends a PDF fleet report every Monday describing degraded disks, changes, and what to replace.prefail.io · read 8 Oct 2026
- Scoring
- Its SENTINEL scoring weighs 25+ S.M.A.R.T. attributes and gives each disk a 0–100 risk score.prefail.io · read 8 Oct 2026
- Transport security
- Prefail says data is sent over TLS using a per-server API token bound to machine_id, with independent authentication for each server.prefail.io · read 8 Oct 2026
- Trend analysis
- Prefail shows score history with 7-day deltas and classifies signals as stable or rising.prefail.io · read 8 Oct 2026
- Upcoming features
- The site lists maintenance windows, REST API, webhooks, and team access as coming in Q2–Q3 2026 for Business tier and above.prefail.io · read 8 Oct 2026
