OJS Migration Guides
This section provides detailed, version-specific migration guides for upgrading Open Journal Systems (OJS) across major and minor releases. Whether you are moving from the legacy OJS 2.x series or stepping through recent 3.x point releases, each guide covers pre-migration checks, data considerations, and post-migration validation.
Focus version
This guidebook targets OJS 3.5.0.4 and later. All migration paths below ultimately aim to bring your installation to a supported, current release.
Available Guides
| Migration Path | Guide |
|---|---|
| OJS 2.x → OJS 3.3 | Read guide → |
| OJS 3.3.x.x → OJS 3.4.y.y | Read guide → |
| OJS 3.5.0.x → OJS 3.5.0.4 | Read guide → |
| Plugin Upgrade Guide | Read guide → |
Migration Philosophy
OJS uses a sequential upgrade model — you cannot skip major versions. If you are running OJS 2.4.x, you must first migrate to OJS 3.3, then to 3.4, and finally to 3.5. Attempting to jump multiple major versions in one step is not supported and will cause data corruption.
General Principles
- Back up everything before touching a production server.
- Test on a staging clone before applying to production.
- Read the release notes for each version you are crossing.
- Upgrade plugins separately after each OJS version upgrade.
- Allow adequate downtime — migrations across major versions can take 30–90 minutes on a typical installation.
Recommended Migration Path (2024–2026)
OJS 2.4.x
↓ migrate-ojs2-to-ojs33
OJS 3.3.0-19 (latest 3.3 release)
↓ migrate-ojs33-to-ojs34
OJS 3.4.0-8 (latest 3.4 release)
↓ site-admin/upgrade guide
OJS 3.5.0.x
↓ migrate-ojs350x-to-ojs3504
OJS 3.5.0.4 ✅ (current recommended)
Further Reading
- PKP Upgrading OJS Documentation — official PKP guides
- OJS Release Notes (GitHub) — changelog for every release
- PKP Community Forum – Upgrades — community Q&A
- Upgrading OJS (Site Admin Guide) — general upgrade procedure