Moodle on Google Cloud Run

Moodle is the world's most popular open-source Learning Management System (LMS), used by universities, schools, corporations, and online training providers worldwide. This module deploys Moodle on Cloud Run v2 on top of the App_CloudRun foundation, which provisions and manages the shared Google Cloud infrastructure.

This guide focuses on the cloud services Moodle uses and how to explore and operate them from the Google Cloud Console and the command line. For the mechanics common to every Cloud Run application — service identity, ingress and load balancing, scaling and concurrency, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC Service Controls, backups, and the deployment lifecycle — refer to the App_CloudRun foundation guide rather than repeating them here.

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1. Overview

Moodle runs as a PHP 8.3/Apache container on Cloud Run v2. The deployment wires together a focused set of Google Cloud services:

Capability	Google Cloud service	Notes
Compute	Cloud Run v2	PHP 8.3/Apache service, 1 vCPU / 2 GiB by default, request-based autoscaling
Database	Cloud SQL for PostgreSQL 15	Required — Moodle does not support MySQL in this deployment
Shared files	Filestore (NFS)	Moodle moodledata directory shared across all instances; mandatory
Object storage	Cloud Storage	A data bucket and any additional user-defined buckets
Cache & sessions	Redis	Enabled by default; required for multi-instance PHP session consistency
Secrets	Secret Manager	Auto-generated cron password, SMTP password, and database password
Scheduler	Cloud Scheduler	Auto-provisioned cron job (every minute) against /admin/cron.php
Ingress	Cloud Run URL / Cloud Load Balancing	Default run.app URL, optional external HTTPS load balancer + custom domain

Sensible defaults worth knowing up front:

• PostgreSQL 15 is mandatory. The database engine is fixed and MOODLE_DB_TYPE = "pgsql" is hardcoded; selecting MySQL or NONE breaks startup.
• NFS is mandatory. The Moodle moodledata directory must be a shared writable filesystem accessible across all instances. enable_nfs defaults to true and requires execution_environment = "gen2".
• The startup probe is HTTP targeting /health.php. Unlike some PHP applications that issue HTTP→HTTPS redirects, Apache in this deployment binds on port 8080 without redirect, so an HTTP probe against /health.php returns 200 directly.
• Redis is enabled by default. Without a shared session store, users are logged out when a request reaches a different Cloud Run instance.
• A Cloud Scheduler job is auto-provisioned. It fires every minute to /admin/cron.php using a secure, auto-generated cron password stored in Secret Manager.
• The cron password and SMTP password are generated automatically and stored in Secret Manager; you never set them in plain text.

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2. Google Cloud Services & How to Explore Them

All commands assume PROJECT and REGION are set. Service and resource names are reported in the deployment Outputs.

A. Cloud Run — the Moodle service

Moodle runs as a stateless Cloud Run v2 service. Request-based autoscaling adds instances under load and, with min_instance_count = 0, scales to zero between sessions (development) or keeps a warm instance when set to 1 (production).

• Console: Cloud Run → select the Moodle service for logs, revisions, metrics, and configuration.
• CLI:

  gcloud run services list --region "$REGION" --project "$PROJECT"
  gcloud run services describe <service-name> --region "$REGION" --project "$PROJECT"
  gcloud run revisions list --service <service-name> --region "$REGION" --project "$PROJECT"
  # Stream recent logs:
  gcloud logging read \
    'resource.type="cloud_run_revision" AND resource.labels.service_name="<service-name>"' \
    --project "$PROJECT" --limit 50 --order asc

See App_CloudRun for scaling, concurrency, and traffic split details.

B. Cloud SQL for PostgreSQL 15

Moodle stores all application data (courses, users, grades, activity logs) in a managed Cloud SQL for PostgreSQL 15 instance. Each Cloud Run instance connects privately through the Cloud SQL Auth Proxy sidecar over a Unix socket, so no public IP is exposed. On first deploy an initialization job creates the database and user and enables the pg_trgm extension for Moodle's full-text search.

• Console: SQL → select the instance for connections, backups, flags, and metrics.
• CLI:

  gcloud sql instances list --project "$PROJECT"
  gcloud sql instances describe <instance-name> --project "$PROJECT"
  # Open an interactive shell to inspect schema/data:
  gcloud sql connect <instance-name> --user=<db-user> --database=<db-name> --project "$PROJECT"

The instance name, database name, user, and the Secret Manager secret holding the password are all surfaced in the Outputs. For the connection model, automated backups, and password rotation, see App_CloudRun.

C. Filestore (NFS) and Cloud Storage

Moodle's moodledata directory is written to a Filestore (NFS) share mounted into every Cloud Run instance so all instances see the same uploaded files, course materials, and user submissions. A dedicated Cloud Storage data bucket is also provisioned; the service account is granted access automatically.

NFS volume mounts require execution_environment = "gen2" (the default).

• Console: Filestore → Instances for the NFS share; Cloud Storage → Buckets for the data bucket.
• CLI:

  gcloud filestore instances list --project "$PROJECT"
  gcloud storage buckets list --project "$PROJECT"
  gcloud storage ls gs://<data-bucket>/          # bucket name is in the Outputs

See App_CloudRun for NFS provisioning, GCS Fuse, and CMEK options.

D. Redis cache

Redis backs Moodle's PHP session handling and application cache. When no external Redis host is configured and NFS is enabled, the NFS host IP is used as the Redis endpoint — suitable for development. For production with multiple instances, set redis_host to a Cloud Memorystore instance IP.

• Console: Memorystore → Redis (if using a managed instance).
• CLI:

  redis-cli -h <redis-host> ping           # from a host with network access
  redis-cli -h <redis-host> info keyspace

E. Secret Manager

The Moodle cron password and SMTP password are generated automatically by Moodle_Common and stored as Secret Manager secrets. The database password is generated and managed by the foundation. All three are injected into Cloud Run instances at runtime; plaintext never appears in configuration files.

• Console: Security → Secret Manager.
• CLI:

  gcloud secrets list --project "$PROJECT"
  gcloud secrets versions access latest --secret=<secret-name> --project "$PROJECT"

The database password secret name is in the Outputs. After deployment, update the SMTP password secret with your real SMTP credential:

echo -n "your-smtp-password" | \
  gcloud secrets versions add <smtp-password-secret> --data-file=- --project "$PROJECT"

See App_CloudRun for rotation details.

F. Cloud Scheduler

A Cloud Scheduler job is auto-provisioned on every deployment to drive Moodle's internal task queue. It fires every minute and authenticates using the auto-generated MOODLE_CRON_PASSWORD.

• Console: Cloud Scheduler → Jobs.
• CLI:

  gcloud scheduler jobs list --project "$PROJECT"
  gcloud scheduler jobs describe <job-name> --location "$REGION" --project "$PROJECT"
  # Manually trigger a cron run:
  gcloud scheduler jobs run <job-name> --location "$REGION" --project "$PROJECT"

G. Networking & ingress

By default Moodle is accessible via the Cloud Run-managed run.app URL. An optional HTTPS load balancer with Cloud Armor and a custom domain can be enabled. Setting application_domains automatically injects MOODLE_REVERSE_PROXY = "true" and ENABLE_REVERSE_PROXY = "TRUE" so Moodle generates correct HTTPS URLs behind the load balancer.

• Console: Cloud Run → select the service → Networking; Network services → Load balancing (if using Cloud Armor).
• CLI:

  gcloud run services describe <service-name> --region "$REGION" --project "$PROJECT" \
    --format="value(status.url)"
  gcloud compute forwarding-rules list --project "$PROJECT"     # if LB is enabled

See App_CloudRun for custom domains, Cloud CDN, and static IP details.

H. Cloud Logging & Monitoring

Cloud Run instance stdout/stderr flow to Cloud Logging; request metrics and Cloud SQL metrics flow to Cloud Monitoring. Optional uptime checks and alert policies are available.

• Console: Logging → Logs Explorer; Monitoring → Dashboards / Alerting.
• CLI:

  gcloud logging read \
    'resource.type="cloud_run_revision" AND resource.labels.service_name="<service-name>"' \
    --project "$PROJECT" --limit 50

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3. Moodle Application Behaviour

• First-deploy database setup. Two initialization jobs run before the Cloud Run service becomes live. The db-init job creates the Moodle database and user, enables the pg_trgm extension, and grants privileges (idempotent, safe to re-run). The nfs-init job creates the required Moodle subdirectories (filedir, temp, cache, localcache) on the NFS share and sets www-data ownership.
• Automatic cron scheduling. A Cloud Scheduler job fires every minute targeting /admin/cron.php?password=<MOODLE_CRON_PASSWORD>. This drives all Moodle scheduled tasks: course backups, email notifications, badge processing, and activity completions. The job is always created and cannot be disabled.
• Health path. Startup and liveness probes use HTTP /health.php, which returns HTTP 200 when PHP is operational. The startup probe allows up to 10 minutes (failure_threshold = 20, period_seconds = 30) for first-boot schema creation and plugin registration.
• SMTP outbound email. SMTP settings are injected as environment variables. Override the defaults using environment_variables (see Group 6). The SMTP password is auto-generated and stored in Secret Manager; update the secret with your real credential after deployment.
• wwwroot resolution. Moodle's config.php resolves wwwroot from the APP_URL environment variable, falling back to CLOUDRUN_SERVICE_URL. When application_domains is set, MOODLE_REVERSE_PROXY and ENABLE_REVERSE_PROXY are automatically set to "true" / "TRUE" so Moodle generates correct HTTPS URLs behind the load balancer.
• Scale-to-zero. min_instance_count = 0 is the default; the first request after idle will cold-start the PHP/Apache container. Set min_instance_count = 1 in production to eliminate cold-start latency for students.
• Admin login. The initial admin username and email are configurable via environment_variables. The admin password is set during Moodle's first install via admin/cli/install_database.php.

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4. Configuration Variables

Variables are grouped exactly as they appear on the deployment platform. Only settings specific to or notable for Moodle are listed; every other input is inherited from App_CloudRun with its standard behaviour and defaults.

Group 1 — Project & Identity

Variable	Default	Description
project_id	(required)	Target Google Cloud project.
region	us-central1	Region for the service and regional resources.

Group 2 — Deployment Environment

Variable	Default	Description
tenant_deployment_id	demo	Short suffix that makes resource names unique per environment.
support_users	[]	Emails granted project access and monitoring alerts.
resource_labels	{}	Labels applied to all resources for cost/ownership tracking.

Group 3 — Application Identity

Variable	Default	Description
application_name	moodle	Base name for resources. Do not change after first deploy.
display_name	Moodle LMS	Friendly name shown in the Console.
description	Moodle LMS - Online learning and course management platform	Service description annotation.
application_version	4.5.1	Container image version tag; increment to roll out a new version.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
cpu_limit	1000m	CPU per instance. Increase to 2000m for production with concurrent students.
memory_limit	2Gi	Memory per instance; 2 GiB provides headroom for PHP with OPcache.
min_instance_count	0	Minimum live instances. Set to 1 to eliminate cold-start latency.
max_instance_count	3	Maximum concurrent instances.
container_port	8080	Moodle/Apache listens on port 8080.
execution_environment	gen2	Required for NFS volume mounts.
timeout_seconds	300	Maximum request duration; increase up to 3600 for large file uploads.
enable_image_mirroring	false	Disabled — Moodle uses a custom Dockerfile with no external prebuilt image.

Group 5 — Networking

Variable	Default	Description
ingress_settings	all	"all" allows public internet traffic. Use "internal-and-cloud-load-balancing" when Cloud Armor is in front.
vpc_egress_setting	PRIVATE_RANGES_ONLY	Routes only RFC 1918 traffic via the VPC connector.

Group 6 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{}	Extra non-secret settings. Override auto-injected SMTP defaults here (e.g., MOODLE_SMTP_HOST, MOODLE_ADMIN_EMAIL).
secret_environment_variables	{}	Map of env var → Secret Manager secret name.
secret_propagation_delay	30	Seconds to wait after secret creation before proceeding.

Group 7 — Backup & Recovery

Variable	Default	Description
backup_schedule	0 2 * * *	Automated backup cron (UTC).
backup_retention_days	7	Retention; raise to 30–90 for production/compliance.
enable_backup_import / backup_source / backup_uri	restore options	Restore from a backup on deploy.

Group 8 — CI/CD & GitHub Integration

Standard App_CloudRun Cloud Build / Cloud Deploy integration — see App_CloudRun. Key inputs: enable_cicd_trigger, github_repository_url, github_token, enable_cloud_deploy.

Group 9 — Custom SQL Scripts

enable_custom_sql_scripts, custom_sql_scripts_bucket, custom_sql_scripts_path, custom_sql_scripts_use_root — run SQL from a GCS bucket after provisioning. Use this to install additional PostgreSQL extensions or seed data. See App_CloudRun.

Group 10 — Security, Storage & Images

Variable	Default	Description
enable_cloud_armor	false	Attach a Cloud Armor WAF + HTTPS load balancer.
application_domains	[]	Custom domain names; also activates MOODLE_REVERSE_PROXY = "true".
enable_cdn	false	Enable Cloud CDN on the load balancer.
create_cloud_storage	true	Provision the data bucket.
storage_buckets	[{ name_suffix = "data" }]	Additional GCS buckets to provision.

Group 11 — Filesystem (NFS) & Cloud Storage

Variable	Default	Description
enable_nfs	true	Shared Filestore volume for Moodle moodledata (keep enabled — required for all deployments).
nfs_mount_path	/mnt/nfs	Container path where the NFS share is mounted; injected as MOODLE_DATA_DIR.
gcs_volumes	[]	GCS Fuse volume mounts for themes or plugins.

Group 12 — Database Backend

Variable	Default	Description
database_type	POSTGRES_15	Fixed at PostgreSQL 15 — do not change.
db_name	moodle	Database name. Immutable after first deploy.
db_user	moodle	Application database user. Immutable after first deploy.
database_password_length	32	Generated password length.
enable_auto_password_rotation	false	Zero-downtime DB password rotation.

Group 13 — Jobs

Variable	Default	Description
initialization_jobs	[]	Leave empty to use the built-in db-init and nfs-init jobs.
cron_jobs	[]	Supplemental Cloud Run Jobs triggered by Cloud Scheduler (the Moodle cron scheduler job is always created separately).

Group 14 — Observability & Health

Variable	Default	Description
startup_probe	HTTP /health.php, 20 failures × 30 s	Up to 10 minutes for Moodle to complete first-boot setup.
liveness_probe	HTTP /health.php, 120 s initial delay	Periodic health check after startup.
uptime_check_config	disabled, path /	Optional Cloud Monitoring uptime check.
alert_policies	[]	Optional metric alert policies.

Group 21 — Redis Cache

Variable	Default	Description
enable_redis	true	Use Redis for PHP sessions and Moodle application cache.
redis_host	""	Leave empty to use the NFS host IP (development only); set to a Cloud Memorystore IP for production.
redis_port	6379	Redis port (string type).
redis_auth	""	Optional Redis auth password (sensitive).

Group 22 — VPC Service Controls & Audit Logging

Variable	Default	Description
enable_vpc_sc	false	Enforce a VPC-SC perimeter (requires organization_id).
vpc_cidr_ranges / vpc_sc_dry_run	(set)	Access level CIDRs / dry-run mode.
enable_audit_logging	false	Detailed Cloud Audit Logs.

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5. Outputs

These values are returned on a successful deployment and are the quickest way to locate and explore the running resources.

Output	Description
service_name	Cloud Run service name.
service_url	Default run.app URL to reach Moodle.
service_location	Cloud Run service region.
stage_services	URLs of stage-specific service revisions (when Cloud Deploy is enabled).
load_balancer_ip	External load balancer IP (when Cloud Armor + custom domain is enabled).
load_balancer_url	HTTPS URL via the load balancer.
database_instance_name	Cloud SQL instance name.
database_name	Application database name.
database_user	Application database user.
database_password_secret	Secret Manager secret holding the DB password.
database_host / database_port	DB host (sensitive) / port.
storage_buckets	Created Cloud Storage buckets.
network_name / network_exists / regions	VPC network, presence, available regions.
nfs_server_ip	Private IP of the Filestore NFS server (sensitive).
nfs_instance_tags	GCE network tags on the NFS instance.
nfs_mount_path	Container path where the NFS share is mounted.
nfs_share_path	Export path on the NFS server.
container_image / container_registry	Deployed image and Artifact Registry repo.
monitoring_enabled / monitoring_notification_channels	Monitoring status and channels.
uptime_check_names	Names of the Cloud Monitoring uptime checks.
initialization_jobs / nfs_setup_job	Names of the setup and NFS init jobs.
deployment_id / tenant_id / resource_prefix	Naming identifiers.
project_id / project_number	Project identifiers.
cicd_enabled / cicd_configuration	CI/CD status and details (repo, trigger, registry).
vpc_sc_enabled / vpc_sc_perimeter_name / vpc_sc_dry_run_mode	VPC-SC status.
audit_logging_enabled / artifact_registry_cmek_enabled	Audit logging and CMEK status.

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6. Configuration Pitfalls & Sensible Defaults

Risk: Critical (data loss / outage / security) — High (service degraded) — Medium (cost or partial degradation) — Low (minor).

Setting	Sensible value	Risk	Consequence if wrong
database_type	POSTGRES_15	Critical	Moodle requires PostgreSQL; MOODLE_DB_TYPE = "pgsql" is hardcoded — any other engine breaks startup.
enable_nfs	true	Critical	Without shared NFS storage, moodledata is not shared across instances and uploads are lost on restart.
execution_environment	gen2 (default)	Critical	NFS volume mounts are not supported in gen1; the service will not start with NFS enabled.
db_name / db_user	set once	Critical	Immutable after first deploy; renaming recreates the DB/user and destroys data.
enable_backup_import	false unless restoring	Critical	Enabling without a valid backup_uri fails the import job.
enable_redis	true	High	Without a shared session store, users on multi-instance deployments are logged out on each new instance.
redis_host	"" (NFS) or explicit	High	No valid endpoint if Redis is on but NFS is off and no host is set.
memory_limit	2Gi	High	Too little memory causes PHP OOM during course imports or large file uploads.
min_instance_count	1 for production	High	0 causes cold-start delays; the Cloud Scheduler cron job may time out waiting for the first request to warm the instance.
nfs_mount_path	/mnt/nfs	High	Must match MOODLE_DATA_DIR; changing after first deploy moves the data root and breaks the installation.
application_domains + MOODLE_REVERSE_PROXY	set together	High	Without the reverse proxy flags, Moodle generates HTTP URLs behind an HTTPS load balancer, breaking links and logins.
enable_cloud_armor / enable_iap	enable for admin-facing	Medium	The admin UI is otherwise publicly reachable.
backup_retention_days	7 (raise for prod)	Medium	Too short for compliance retention.
max_revisions_to_retain	7	Low	Unlimited retained revisions can accumulate over time.

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For the foundation behaviour referenced throughout — service identity, ingress and load balancing, scaling and concurrency, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC-SC, backups, and image lifecycle — see App_CloudRun. Moodle-specific shared configuration is described in Moodle_Common.