btrfs-backup-ng-verify - Man Page

btrfs-backup-ng verify [Options] LOCATION

Verify that backups at a given location are valid and restorable. This command provides multiple levels of verification to check backup integrity, from quick metadata checks to full restore tests.

Verification works with both local backup directories and remote SSH locations.

LOCATION

Backup location to verify. Can be a local path (e.g., /mnt/backup/home) or an SSH URL (e.g., ssh://user@host:/path/to/backup).

--level LEVEL

Verification level. Default: metadata. Valid levels:

metadata

Quick check of snapshot existence and parent chain integrity. Verifies that all snapshots exist and that incremental chains are complete (no missing parent snapshots). This is fast and non-destructive.

stream

Verify that btrfs send stream can be generated. Uses btrfs send --no-data to test stream generation without transferring actual file data. This validates that snapshot metadata is intact.

full

Complete restore test to a temporary location. Actually restores snapshot(s) and verifies the restored subvolume is valid. This is the most thorough check but also the slowest. Requires --temp-dir for remote backups.

--snapshot NAME

Verify only the specified snapshot instead of all snapshots.

--temp-dir PATH

Temporary directory for full verification. Must be on a btrfs filesystem. Required for full verification of remote backups.

--no-cleanup

Do not delete restored snapshots after full verification. Useful for inspection or debugging.

--prefix PREFIX

Only verify snapshots matching the given prefix.

--ssh-sudo

Use sudo for btrfs commands on remote host.

--ssh-key FILE

SSH private key file for authentication.

--fs-checks MODE

Filesystem verification mode. Valid values:

auto

(Default) Warn about issues but continue operation.

strict

Error out on filesystem check failures.

skip

Bypass all filesystem verification checks.

--no-fs-checks

Skip btrfs subvolume verification checks. Alias for --fs-checks=skip. Useful when verifying backup directories which are regular directories, not subvolumes.

--json

Output results in JSON format for scripting and automation.

-q,  --quiet

Suppress progress output.

0

All verifications passed.

1

One or more verifications failed.

2

Error during verification (could not complete).

Quick metadata check of local backup:

btrfs-backup-ng verify /mnt/backup/home

Verify remote backup over SSH:

btrfs-backup-ng verify ssh://backup@server:/backups/home --ssh-sudo

Stream integrity check:

btrfs-backup-ng verify /mnt/backup/home --level stream

Full restore test:

btrfs-backup-ng verify /mnt/backup/home --level full --temp-dir /mnt/test

Full verification of remote backup:

btrfs-backup-ng verify ssh://server:/backups/home --level full --temp-dir /mnt/test

Verify specific snapshot:

btrfs-backup-ng verify /mnt/backup/home --snapshot home-20260104-120000

JSON output for automation:

btrfs-backup-ng verify /mnt/backup/home --json

The verify command displays a table of results showing:

• Snapshot name
• Pass/Fail status
• Details (parent snapshot, error messages)

Summary shows total passed, failed, and duration.

With --json, output is a JSON object containing:

• level: Verification level used
• location: Backup location
• duration_seconds: Total verification time
• summary: Counts of passed, failed, total
• results: Array of individual snapshot results
• errors: Array of error messages

For automated backup verification in scripts or cron:

#!/bin/bash
if ! btrfs-backup-ng verify /mnt/backup/home --json > /tmp/verify.json; then
    # Send alert on failure
    cat /tmp/verify.json | mail -s "Backup verification failed" admin@example.com
fi

btrfs-backup-ng(1), btrfs-backup-ng-restore(1), btrfs-send(8)

btrfs-backup-ng(1), btrfs-backup-ng-doctor(1).