snapraid(1)
snapraid is a backup program that stores redundancy information and can recover corrupted files from disk failures without requiring a full backup copy.
Synopsis
snapraid [COMMAND] [OPTIONS] [ARGS]Description
snapraid is a snapshot-based backup and recovery tool designed for media centers and large file collections. It maintains parity blocks similar to RAID, allowing recovery from disk failures and file corruption without duplicating your entire data.
Unlike traditional RAID, snapraid is not real-time; you run it explicitly to create snapshots and parity data. This makes it suitable for cold storage scenarios where data doesn't change frequently but you want protection against hardware failures and bitrot.
snapraid can recover lost files, detect and fix corrupted data, and provide detailed reports on your storage health.
Common options
| Flag | What it does |
|---|---|
sync | Create or update parity blocks for all new and changed files |
check | Verify parity data and detect any corruption or missing files |
fix | Attempt to recover corrupted or missing files using parity data |
list | List all files in the snapraid filesystem |
status | Display current snapraid status and statistics |
dup | Find duplicate files across the filesystem |
pool | Create a virtual unified view of all snapraid disks |
-c CONFIG | Use alternate configuration file instead of default |
-v | Verbose output; show detailed progress and information |
--dry-run | Simulate operation without making actual changes |
Examples
Create or update all parity blocks for new and changed files since last sync
snapraid syncVerify integrity of all parity data and report any corruption found
snapraid checkAutomatically recover and repair corrupted or missing files using parity data
snapraid fixShow filesystem status using a custom configuration file
snapraid -c /etc/snapraid.conf statusFind and list all duplicate files across all snapraid disks
snapraid dupList all files in snapraid filesystem and filter for video files
snapraid list | grep videoRun sync with verbose output and save results to a log file
snapraid -v sync 2>&1 | tee sync.logPreview what repairs would be made without actually fixing anything
snapraid --dry-run fix