28 August 2026 • NEWS

COMPLETE OJS MIGRATION GUIDE FROM OLD VERSIONS TO 3.5: SAFE STRATEGIES WITHOUT DATA LOSS

Introduction: Why Migrating to OJS 3.5 Now is a Must?

The world of scholarly publishing is constantly evolving, and Open Journal Systems (OJS) must remain relevant and secure. If your journal is still using an older OJS version (e.g., OJS 2.x or early OJS 3.x), it's time to consider migrating to OJS 3.5.x. This latest version offers significant improvements in user interface, more advanced editorial features, better security, and broader compatibility with modern web standards. However, the migration process is often daunting due to concerns about data loss. This article will guide you through the detailed steps to ensure a smooth and secure transition, preserving the integrity of your journal's data.

Key Benefits of OJS 3.5.x:

  • Modern User Interface: Responsive and intuitive design that enhances the user experience for authors, reviewers, and editors.
  • Enhanced Editorial Features: More efficient workflows, better file management capabilities, and flexible publishing scheduling options.
  • Security & Performance: Crucial security updates and performance optimization for a faster and more secure journal.
  • Compatibility & Integration: Support for the latest PHP and database versions, as well as easy integration with various plugins (such as LoA Validator or Midtrans Payment Gateway from OJSPLUGIN.COM) and DOI/ORCID standards.

Migration Preparation: The Foundation of Your Data Security

Before starting the migration process, thorough preparation is key to avoiding unwanted issues. Never underestimate this step.

1. Comprehensive Data Backup

This is the most crucial step. Ensure you have a complete copy of:

  • Database: Use phpMyAdmin or the mysqldump command to export your entire old OJS database. Example: mysqldump -u username -p database_name > backup.sql.
  • OJS Files: Copy all your OJS installation files and folders to a secure location. This includes your web public folder and the files_dir folder (which should be outside your web public directory).

2. Check Server Requirements

OJS 3.5.x has higher system requirements than older versions. Ensure your server meets:

  • PHP: Version 7.4 up to 8.2 (OJS 3.5.x does not support PHP 8.3 and above by default).
  • MySQL/MariaDB: Version 5.7+ or PostgreSQL 9.5+.
  • Required PHP Extensions: Ensure extensions like mbstring, gd, xml, curl, intl, json, zip, etc., are active.
  • PHP Memory Limit: Increase memory_limit in your php.ini, at least 256MB, ideally 512MB or more.

3. Plan the Upgrade Path

OJS does not always allow direct upgrades from very old versions. For example, if you are still on OJS 2.x, you might need to upgrade to an earlier OJS 3.x version (e.g., 3.1.x or 3.2.x) first before proceeding to 3.5.x. Always check the official OJS documentation for recommended upgrade paths.

4. Deactivate Custom/Non-Standard Plugins

Before migration, deactivate all non-standard or custom plugins. These plugins may not be compatible with OJS 3.5.x and could cause conflicts during the upgrade.

Step-by-Step OJS Migration to Version 3.5.x

With thorough preparation, you are ready to begin the migration process. Follow these steps carefully.

Step 1: Download the Latest OJS 3.5.x Package

Download the latest stable version of OJS 3.5.x from the official PKP (Public Knowledge Project) website. Extract the files to a temporary directory on your server.

Step 2: Prepare the New Installation Directory

Ideally, you would perform the migration in a separate staging environment first. If not, ensure you are working in a new directory or have cleared your old OJS installation directory (after all backups are complete). Copy all files from the downloaded OJS 3.5.x package to the new installation directory.

Step 3: Configure config.inc.php

Copy the config.inc.php file from your old OJS installation to the new OJS 3.5.x installation directory. Open the file and make adjustments:

  • Database: Ensure the database connection information (host, username, password, name) points to your backed-up old OJS database.
  • files_dir: Update the files_dir path to point to your old files_dir folder. Ensure this folder is outside the public web directory for security.
  • installed: Make sure the installed value is Off (or 0) to allow the upgrade process. This will change to On (or 1) after a successful upgrade.

Step 4: Run the Upgrade Script

Open your terminal or SSH into your server and navigate to the new OJS 3.5.x installation directory. Run the upgrade command:

php tools/upgrade.php upgrade

This process will take time depending on your database size and the number of files. Monitor the terminal output for any errors. If errors occur, note them down and address them immediately. Do not proceed if there are fatal errors.

Step 5: Clear Cache and Verify

Once the upgrade script is complete:

  • Manually clear the cache: Delete all files inside the cache/ folder (except index.html) in your OJS installation directory. You can also use the command php lib/pkp/tools/clear_data.php.
  • Access your OJS: Open a browser and access your journal's URL. Verify that OJS is running with version 3.5.x.
  • Check Data Integrity: Log in as an administrator. Check users, submissions, issues, and other journal settings. Ensure everything has migrated correctly. Download a few random articles to confirm PDF/Galley files are still available.

Post-Migration: Optimization and Enhancements

Migration is the first step. Now it's time to optimize your new OJS 3.5.x.

1. Theme and Plugin Installation

OJS 3.5.x is not compatible with OJS 2.x themes or plugins. You will need to find themes and plugins specifically designed for OJS 3.x. Consider premium themes like Aurora Theme or Lumina Theme from OJSPLUGIN.COM for a professional, modern, and responsive look. For additional functionality, you can install plugins like LoA Validator for acceptance letter authentication, or Midtrans Payment Gateway to facilitate payments. OJSPLUGIN.COM offers a range of solutions that can significantly enhance your journal's functionality and aesthetics.

2. Update Journal Settings

Review all journal settings in the administration area, including policies, metadata, and distribution options. Some settings may have changed or have new options in OJS 3.5.x.

3. Full Test Run

Conduct an end-to-end test run: from author registration, article submission, review process, to publication. Involve several users to test different roles (author, reviewer, editor) to ensure all workflows function correctly.

4. Reconfigure Cron Jobs

If you had cron jobs configured for your old OJS (e.g., for scheduled email deliveries or indexing), ensure to update their commands to match the new OJS 3.5.x installation.

5. Consider Professional Assistance

If the migration process is too complex or you encounter unresolved issues, do not hesitate to seek professional help. OJSPLUGIN.COM offers OJS consulting and customization services, including complex data migrations, to ensure your journal runs smoothly and optimally.

Conclusion

Migrating OJS from an old version to 3.5.x is a vital investment for the future of your scholarly journal. With thorough preparation and by following this step-by-step guide, you can perform the upgrade safely and without data loss. After migration, take advantage of OJS 3.5.x's new features and consider premium solutions from OJSPLUGIN.COM, such as professional themes and functional plugins, to elevate your journal to the next level. Security, efficiency, and a modern appearance are key to maintaining your journal's relevance and credibility in the digital age.

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