Prefail

What Prefail is

Prefail monitors S.M.A.R.T. disk health across server fleets and sends alerts about disk problems with recommended actions. Its SENTINEL score weighs more than 25 S.M.A.R.T. attributes and assigns each disk a risk score from 0 to 100. Score history includes seven-day changes and labels signals as stable or rising. Alerts carry a severity, a readable explanation, and an action recommendation; users can acknowledge, mute, or dismiss them in batches. Prefail supports MegaRAID 9260, 9361, and 9460, Adaptec SmartRAID, and Linux mdadm, including individual disk health behind controllers. Notifications include Telegram alerts, a Telegram Mini App dashboard, and email as a fallback. A Monday PDF fleet report summarizes degraded disks, changes, and replacement guidance. The Linux agent runs smartctl and sends its output with curl. Prefail says it collects only S.M.A.R.T. data, transmits it over TLS with a per-server API token, and stores data on a dedicated server in Europe. Plans start with a free tier for up to two servers; paid plans begin at $9 per month. Prefail cautions that S.M.A.R.T. monitoring may miss sudden failures and is not a substitute for backups.

Who it suits

Prefail suits administrators monitoring disk health across Linux server fleets, including supported RAID setups and Linux mdadm. Its alerts, fleet reports, and server-count-based plans are relevant to teams that need visibility across multiple machines.

Limits

The free plan covers up to 2 servers, checks every 30–60 minutes, keeps 7-day score history, and sends email alerts to 1 recipient. Paid plans start at $9.00 per month; the PRO plan covers up to 20 servers, with 5–30 minute checks, 90-day history, 3 email recipients, and a weekly PDF digest.

Getting started

1. Visit prefail.io.
2. Install the Linux agent, which runs smartctl and sends output with curl.
3. Connect supported MegaRAID, Adaptec SmartRAID, or Linux mdadm disks as applicable.
4. Choose the free plan or a paid plan based on server count and monitoring needs.
5. Set up Telegram alerts or use email alerts as a fallback.

Verdict

Choose Prefail if you need S.M.A.R.T.-based disk monitoring, alerts, and fleet reporting for Linux servers. Look elsewhere if you need protection against sudden electrical or controller failures; Prefail explicitly says monitoring does not replace backups.