🛠 Fixing Moodle Admin Errors and Supporting Multi-Tenancy for Ejss App

A Step-by-Step Illustrated Guide for Moodle Administrators

Maintaining Moodle in production sometimes means solving unexpected problems quickly and then adapting to long-term changes. This guide covers two practical fixes:

Problem accessing Site Administration
Supporting multi-tenancy in Ejss App (EJS JavaScript simulations via LTI)

1. 🚨 Problem Accessing Site Administration

The Issue

An unusual file appeared in the Moodle installation:

admin/settings/moodleservices.php

This file prevented administrators from opening the Site Administration menu.

Quick Fix (Terminal Commands)

From your Moodle root directory (/home/iwtstudy/public_html/moodle402):

cd /home/iwtstudy/public_html/moodle402

# Rename the suspicious file
mv admin/settings/moodleservices.php admin/settings/moodleservices.php.off

# Purge Moodle caches
php admin/cli/purge_caches.php

✅ Site Administration became accessible again.

📸 Screenshot after fix (Site Admin working)

Why This Works

Renaming disables the rogue file.
Purging caches clears stale references.

⚠️ Since the origin is unknown, it may reappear. If it does, check:

Recently installed plugins
Custom code commits
Server security logs

2. 🌐 Multi-Tenancy in Ejss App (LTI Integration)

The Ejss App connects to Moodle using LTI. With multi-tenancy, the Deployment ID format changed.

https://community.d2l.com/brightspace/kb/articles/23752-assignments-and-grades-services-extension-with-lti-1-3

link

Old vs New Deployment ID Format

Old (single tenant):

49c45537-c322-45ea-bb7b-b756a2d08bd1

New (multi-tenant, with school code):

49c45537-c322-45ea-bb7b-b756a2d08bd1_0701   (SchoolCode 0701)
49c45537-c322-45ea-bb7b-b756a2d08bd1_0702   (SchoolCode 0702)

📸 Screenshot of Registered Platforms in Moodle (multiple deployment IDs shown)

link

The Problem

Moodle treated each variation as a different deployment, breaking existing integrations.

Code Fix (Patch in Moodle Core)

We modified lib/lti1p3/src/LtiMessageLaunch.php so Moodle ignores the _SchoolCode.

Before (default behavior)

Moodle expected an exact match, so _0701 and _0702 were considered different.

📸 Code diff screenshot (before)

After (patched behavior)

// Deployment ID has new format (OID_SCHOOLID), we only use OID
$deploymentId = $this->jwt['body'][LtiConstants::DEPLOYMENT_ID];
$oid = strstr($deploymentId, '_', true) ?: $deploymentId;
$this->jwt['body'][LtiConstants::DEPLOYMENT_ID] = $oid;

Why This Works

strstr($deploymentId, '_', true) extracts only the original ID before _.
If no _ exists, it keeps the full ID (backward compatible).
Moodle now validates Ejss App consistently across schools.

📸 Screenshot showing Ejss App working again in Moodle

https://vle.sandbox.sls.moe.edu.sg/my-drive/module/view/eb6aaafa-4e1d-472d-802f-949beabb249b/section/28/activity/30?pageNo=1

3. 📝 Key Takeaways

Admin Access Fix: Rogue files like moodleservices.php can break admin. Disable + purge caches to recover.
Multi-Tenancy Fix: New Deployment ID format required a code patch to strip _SchoolCode.
Best Practices:
- Always document quick fixes.
- Clearly comment custom patches for future upgrades.
- Watch Moodle release notes in case an upstream fix arrives.

✅ Conclusion

Running Moodle at scale means handling both unexpected admin errors and external platform changes.

For Site Admin errors, quick terminal fixes restore access.
For Ejss App, a small code change future-proofs Moodle against new Deployment ID formats.

Together, these fixes keep Moodle stable and fully integrated with evolving EdTech platforms.

AI HTML5, Open Source Physics (Easy JavaScript Simulation and Tracker) and TagUI (AI-Singapore)

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Thursday, August 21, 2025