Backup Execution Flow

1

Trigger

Manual click or scheduled cron trigger fires

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2

Create Execution Record

Insert row into job_executions with status "pending"

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3

Connect to Source

Establish connection (local filesystem, SSH, or database)

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4

Determine Backup Strategy

Full backup OR incremental based on last successful backup

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5

Execute Backup

Transfer data, compress, encrypt (if enabled), calculate checksums

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6

Verify & Store

Verify checksum, store metadata in backups table, update execution status

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7

Cleanup & Retention

Apply retention policy, remove old backups, update storage stats

Connection failures: Retry 3x with exponential backoff, then mark as failed
Partial backups: Mark as failed if any source file fails; keep partial for inspection
Storage full: Check before starting, alert if < 10% free space
Checksum mismatch: Delete corrupted backup, retry once, alert admin
Concurrent jobs: Queue or cancel based on resource availability

The system is designed for easy extension:

Backup Flow