Alternative File System Location (local_alternative_file_system)

This plugin allows transferring files from moodledata/filedir to cloud storage and makes Moodle serve/read those files remotely.

Currently supported:

• AWS S3
• DigitalOcean Spaces (S3 compatible)

Why use cloud storage with Moodle

By moving filedir to remote storage (S3/Spaces), you gain:

• Scalability (server disk is no longer a bottleneck)
• Resilience/durability of storage
• Performance via CDN (when applicable)
• Simpler cluster operation (webheads without shared disks)

Implementation

After installing the plugin, you must edit the config.php file and include the following line before the call to require_once( __DIR__ . '/lib/setup.php' );.

$CFG->alternative_file_system_class = "\\local_alternative_file_system\\external_file_system";

Migration

There are two main scenarios:

Scenario A) Migration from local filedir (moodledata/filedir → cloud)

This is the classic scenario:

1. Configure the destination in the plugin (S3/Spaces)
2. Use the plugin's built-in migration mechanism (existing routines/scripts)

Scenario B) Import/Migration from tool_objectfs (ObjectFS → local_alternative_file_system)

Due to user/client requests, support was added to import objects stored in tool_objectfs and copy them to the destination configured in this plugin, enabling migration with minimal downtime.

How the strategy works (without stopping the site)

The migration happens in 2 phases:

Phase 1 — Moodle continues using tool_objectfs (normal production)

While Moodle is configured with:

$CFG->alternative_file_system_class = "\\tool_objectfs\\...";

• The site continues reading/writing normally via tool_objectfs.
• CRON runs a task that copies objects from tool_objectfs to the destination configured in local_alternative_file_system.

In other words: you "duplicate" the objects to the new destination without interrupting the site.

Phase 2 — After copying finishes, switch the AFS to this plugin

When the report indicates that migration is complete (100% / no pending items), change config.php to:

$CFG->alternative_file_system_class = "\\local_alternative_file_system\\external_file_system";

From that point on, Moodle will serve/read files directly through local_alternative_file_system.

Monitoring / Progress Report

Use the plugin's report to track:

• total hashes
• migrated
• missing
• rate (last minutes)
• estimated ETA

Access:

• https://MY-MOODLE/local/alternative_file_system/report-migrate.php

Tip: during Phase 1 (tool_objectfs active), this report helps you decide the right moment to switch $CFG->alternative_file_system_class.

Best practices and notes

• Perform migrations during low-traffic periods.
• Adjust CRON batch sizes/timers according to environment size.
• After switching the AFS to this plugin, monitor the report for a while to ensure there is no "residual queue."
• If you use a CDN, validate headers/content-disposition according to your download policies.