Incident Report: Data Loss During SQLite to PostgreSQL Migration

Summary

During an internal operation aimed at migrating ARAID's persistent storage layer from SQLite to PostgreSQL, a critical failure occurred that resulted in irreversible corruption of all SQLite databases. This event led to a system-wide outage affecting all users.

The failure was triggered by incorrect file access handling, which allowed truncation on production database files prior to data extraction. As a result, PostgreSQL remained empty while the original SQLite files became unreadable and unrecoverable.

Timeline of Contextual Events (No Timestamps)

Below is a sequence of logical events without exact time markers:

1. Migration tool initialized.
2. SQLite files detected and enumerated.
3. Schema transformation routines prepared.
4. SQLite opened with write-enabled mode.
5. Journals invalidated, corruption confirmed.
6. Dump and recovery attempts failed.
7. Global outage recognized due to data unavailability.

What Happened

The goal of the migration was to move away from a file-based storage engine to a client-server relational database for improved performance, concurrency, and reliability. The intended data pipeline was:

However, instead of opening the SQLite database files in a read-only mode, the migration script opened them using:

This permitted truncation prior to journal validation, corrupting the SQLite pages and journals.

Root Cause Analysis

The core issue originated from file handler misuse and lack of defensive data copying. Key points include:

• SQLite was opened in write-enabled mode.
• No snapshot clones were created before processing.
• No rollback mechanism for failed migrations existed.
• No prior backup layer existed for persistent data.

When truncation occurred, the corruption chain looked like this:

After corruption, several recovery attempts were made using:

• PRAGMA integrity_check
• .dump export
• sqldiff
• Forensic page carving

All failed due to invalid headers and incomplete page maps.

Impact

• Complete loss of all stored data.
• Mandatory reconfiguration of every deployment.
• Global downtime affecting every instance of ARAID.
• No usable fallback dataset existed.

Mitigation & Recovery

The following action plan has been adopted:

• Temporary restoration of current ARAID version for continued use.
• All users will need to reconfigure their instance manually.
• ARAID V4 development is being accelerated, partially due to this incident.
• Backup snapshots will become a mandatory prerequisite for future migrations.
• Migrations will run against cloned datasets, never production files.

Looking Forward

We want to make it absolutely clear: this incident will not repeat in the future. This migration failure has prompted structural and architectural changes within ARAID’s ecosystem that enforce:

• Immutable data operations during migrations
• Automated backups and snapshot workflows
• Rollback and recovery paths for every data transformation
• Enhanced peer review and local validation of tooling

Additionally, due to the circumstances and the need for improved reliability, ARAID V4 may be released earlier than initially scheduled to accelerate transition into a safer and more scalable environment.

Lessons Learned

• Data must never be transformed directly within production files.
• Every migration requires the existence of a reversible path.
• SQLite is not suitable as sole production storage without backup workflows.
• Resilience must be designed, not assumed.

Accountability & Apology

I want to take clear and direct responsibility for this failure. There were no external causes, no hardware malfunctions, no cloud provider incidents, and no malicious activity involved. This was the result of an internal mistake on my part, and I take full ownership of its consequences.

I sincerely apologize to all affected users and administrators. Reliability is a core expectation, and this incident fell short of that standard. The frustration and inconvenience caused are valid and understood.