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LimeSurvey on Google Cloud Run

LimeSurvey on Google Cloud Run

LimeSurvey is a free, open-source (GPL) online survey and questionnaire platform written in PHP, supporting unlimited surveys, conditional branching, quotas, and multi-language questionnaires with exportable results. This module deploys LimeSurvey 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 LimeSurvey 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.


What LimeSurvey costs on RAD, and how that compares​

LimeSurvey on RAD's Cloud Run module costs about US$84 a month in a Google Cloud project you own, plus a one-off 75-credit (US$7.50) module fee. LimeSurvey itself is free and open source (GPL), so this is the infrastructure cost of your own, unlimited-response instance rather than a licence. If you only need it occasionally — a single study, a seasonal survey round — a RAD-managed project can be deleted and restored within 30 days for a handful of credits, so that US$84 becomes a few dollars a month instead. See Pause it for free, below.

What you pay on RAD​

In a Google Cloud project you ownIn a project RAD manages for you
Module fee, once per deployment75 credits (US$7.50 at the top-up price)67.5 credits (10% lower)
Build timeA few credits per buildThe same
Google Cloud running costBilled by Google to your own billing account, about US$84 a month for the default configuration (table below)Metered hourly in credits; RAD publishes 32 credits a day, about 960 a month (about US$96 at the top-up price, US$77 at the Scale plan's rate)
Who owns whatYou own the project and its billing; RAD deploys and updates itRAD owns the project, with guardrails, quotas and budget alerts; you get console access, and a minimum purchased balance is held in reserve

10 credits cost US$1 on a one-off top-up, and less on a monthly plan. In a project RAD manages, the database, file server and network are shared by every application in the project, so a second application does not add a second database.

Default running cost in your own project (us-central1, Google list prices):

Resource (module default)Per month
Cloud Run, 1x vCPU / 2 GiB (scaleToZero)US$13.16
Cloud SQL for MySQL, 1 vCPU / 3.75 GB, zonal, 10 GB SSDUS$51.02
NFS/cache file server (small VM)US$13.43
Cloud NAT and networkingUS$5.00
Cloud Storage (add-ons, backups)US$1.00
Totalabout US$84

How it compares​

  • LimeSurvey's own project sells hosted LimeSurvey Cloud at limesurvey.org/pricing: Basic is £66/month (1,000 responses/month, 250 MB, 1 admin); Expert is £30/month billed annually (10,000 responses/year, 1 GB, 3 admins); Business is £64/month billed annually (50,000 responses/year, 3 GB, 5–10 admins); Corporate is custom-priced with SSO/LDAP/SAML.
  • Expert, at around US$38/month, undercuts RAD's US$84 for light, capped use. RAD's advantage grows once you need more than 10,000 responses a year, more than three admins, or want no response/storage ceiling at all — none of which the hosted plans below Corporate offer.
  • A bare VPS (Hetzner CPX22 or DigitalOcean 2 vCPU/4 GB, about US$24/month) undercuts both in cash, with the usual trade-off of running MySQL, backups and patches yourself.
  • See the GKE guide if you'd rather run it alongside other Kubernetes workloads.

Pause it for free: delete a RAD-managed project, restore it when you need it​

If LimeSurvey runs in a project RAD manages for you, you have a second option that goes well beyond scaling to zero: delete the whole project, and restore it within 30 days for close to nothing. This suits LimeSurvey you only need occasionally — a course project, a demo, a short-lived evaluation — far better than running it continuously.

  • How it works. Deleting a RAD-managed project unlinks its billing first, then asks Google to delete the project. Google does not remove the project immediately: it keeps it, recoverable, for 30 days. Because billing is already unlinked, nothing is charged while it waits. Unlike deleting one module, this does not tear down Cloud SQL, any VM or LimeSurvey's own compute one by one — the whole project, and everything in it, simply stops.
  • Restoring costs a handful of credits, not a rebuild. Within 30 days, the project's owner can restore it. RAD asks Google to undelete the project and reattaches its billing account, then asks you to run Update on each deployment to confirm everything came back. Because nothing was individually destroyed, that Update finds the same resources already there — it is a check, not a rebuild, and an Update never charges the module fee again. For LimeSurvey behind a small Services_GCP and Project_GCP, that is a handful of credits (under US$1) in total, against the 80 credits a full redeploy costs.
  • What this needs. You must own the project (not a bring-your-own one RAD only manages billing for), and you restore it yourself within the 30 days — after that, Google deletes it for good. Restoring is admitted like creating a new project: your purchased credit balance must still clear the tier's floor (100 credits for the sandbox tier most study and demo use fits). Google says most services are fully working again within 36 hours of a restore.
  • One real gap: the backup bucket does not survive. LimeSurvey's nightly backups are written to a bucket inside the project, and that bucket is not protected by Cloud Storage's soft-delete, so it is very likely gone as soon as you delete the project — even though the project itself is recoverable for 30 days. If you've customised LimeSurvey and want to keep that work, copy a backup out (to Google Drive, or a bucket outside the project) before you delete, the same as the redeploy workflow below. For a default installation with nothing irreplaceable in it, this does not matter.

Pay only while you use it, the other way: delete and redeploy​

Cloud Run already scales to zero between requests. The option above only applies to a RAD-managed project; in your own project, or once the 30-day window has passed, the way to stop paying is to delete the deployment and deploy it again when you need it.

  • What a redeploy costs. The module fee again plus the builds: about 80 credits (US$8.00), because RAD recreates the project and shared services before LimeSurvey. Deleting saves money only once LimeSurvey would otherwise sit unused for about three days or more, both in your own project (about US$2.79 a day) and in a RAD-managed one (32 credits a day).
  • Delete everything LimeSurvey uses. Most of the running cost is usually the database and the shared file/cache VM. They stop only when nothing else in the project uses it, so deleting LimeSurvey while something else shares the project saves only LimeSurvey's own compute part.
  • Keep your data first. Nightly backups go to a bucket inside the deployment and are deleted with it, so copy the latest backup out before deleting if you want to keep it.

Lab sessions and Managed Environments​

  • Lab sessions, for training. A trainer runs a LimeSurvey session for a class. Each participant gets LimeSurvey in their own Google Cloud project for 15 minutes to 24 hours, within an allowance the trainer sets. Either the trainer funds every place up front, or each participant pays for their own. Everything is deleted when the session ends, and unused credits go back to the trainer.
  • Managed Environments, for consultancies. A partner runs LimeSurvey for a client from a ring-fenced wallet it funds, and settles with the client directly. If the wallet runs low, billing pauses and the data is kept, so nobody receives an unexpected charge. At the end of the engagement the partner hands the project over, and the deployments become the client's own.

Credits can be bought in more than 20 currencies, including XAF, XOF, NGN, GHS, KES and ZAR, by card, bank transfer or mobile money.

Sources (8 October 2026): Google Cloud list prices from the Cloud Billing Catalog API; RAD fees and the 32-credit daily estimate from radmodules.dev/pricing; Delete and restore projects for the 30-day recovery window and what it says about Cloud Storage objects without soft delete. LimeSurvey Cloud pricing. Prices change; check each source before relying on a figure.

1. Overview​

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

CapabilityGoogle Cloud serviceNotes
ComputeCloud Run v2PHP/Apache service on port 8080, 1 vCPU / 2 GiB by default; scale-to-zero supported
DatabaseCloud SQL for MySQL 8.0Required — the engine is fixed and InnoDB is forced
File persistenceCloud Filestore (NFS)Persists /var/www/html/upload across restarts; enabled by default
Object storageCloud StorageA dedicated limesurvey-uploads bucket provisioned automatically
Cache (optional)RedisOptional object cache; disabled by default
SecretsSecret ManagerAuto-generated ADMIN_PASSWORD; database password
IngressCloud Run URL / Cloud Load BalancingDefault run.app URL; optional external HTTPS load balancer + custom domain

Sensible defaults worth knowing up front:

  • MySQL 8.0 is mandatory and InnoDB is forced. The engine is fixed by the shared application layer (database_type = MYSQL_8_0). InnoDB is forced because Cloud SQL disables MyISAM — the image's MyISAM default would otherwise fail table creation on first boot.
  • The schema is created on first container start, not by a migration job. The db-init job only provisions an empty database + user; the upstream LimeSurvey console installer then builds the schema when the app boots. Allow generous startup time on the first deploy.
  • ADMIN_PASSWORD is generated automatically and stored in Secret Manager. The container refuses to start without it. The first super-admin is seeded as admin / admin@techequity.cloud.
  • Cloud SQL is reached over TCP by default (enable_cloudsql_volume = false) — LimeSurvey dials the Cloud SQL private IP over private networking; MySQL over private-IP TCP needs no SSL.
  • NFS is enabled by default (enable_nfs = true) so uploaded assets survive container restarts. Requires the gen2 execution environment (the default).
  • Scale-to-zero is enabled by default (min_instance_count = 0) with max_instance_count = 1. Cold starts add latency after idle; set min_instance_count = 1 to keep the service always warm.
  • PUBLIC_URL is set from the service URL at plan time and corrected at runtime by the container entrypoint, so survey links and assets resolve on the real host.
  • Public ingress is the default (ingress_settings = "all") so respondents can reach public surveys. Enabling IAP will block anonymous respondents.

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 LimeSurvey service​

LimeSurvey runs as a Cloud Run v2 service that autoscales by request load between the minimum and maximum instance counts. Each deployment creates an immutable revision; traffic can be split across revisions for safe rollouts.

  • Console: Cloud Run → select the service for revisions, traffic, logs, and metrics.
  • CLI:
    gcloud run services list --project "$PROJECT" --region "$REGION"
    gcloud run services describe <service-name> --project "$PROJECT" --region "$REGION"
    gcloud run revisions list --service <service-name> --project "$PROJECT" --region "$REGION"

See App_CloudRun for scaling, concurrency, execution environment, and traffic splitting.

B. Cloud SQL for MySQL 8.0​

LimeSurvey stores all application data (surveys, questions, responses, users, global settings) in a managed Cloud SQL for MySQL 8.0 instance. By default the service connects over private-IP TCP (enable_cloudsql_volume = false); no public IP is exposed. On first deploy the db-init Job creates the application database and user; the schema is then built by LimeSurvey's own installer on container start.

  • Console: SQL → select the instance for connections, backups, flags, metrics.
  • CLI:
    gcloud sql instances list --project "$PROJECT"
    gcloud sql instances describe <instance-name> --project "$PROJECT"
    gcloud sql connect <instance-name> --user=<db-user> --database=<db-name> --project "$PROJECT"

The instance name, database, user, and password secret are in the Outputs. See App_CloudRun for the connection model, backups, and password rotation.

C. Cloud Filestore (NFS)​

Enabled by default, a Cloud Filestore (NFS) instance is mounted into the service so LimeSurvey's upload directory (/var/www/html/upload — asset images, signatures, barcodes, uploaded response files) persists across container restarts and revisions. NFS mounts require the gen2 execution environment.

  • Console: Filestore → Instances.
  • CLI:
    gcloud filestore instances list --project "$PROJECT"

See App_CloudRun for the shared-NFS discovery model.

D. Cloud Storage​

A dedicated Cloud Storage bucket (limesurvey-uploads) is provisioned automatically. Additional buckets can be declared via storage_buckets.

  • Console: Cloud Storage → Buckets.
  • CLI:
    gcloud storage buckets list --project "$PROJECT"
    gcloud storage ls gs://<uploads-bucket>/ # bucket name is in the Outputs

See App_CloudRun for GCS Fuse and CMEK options.

E. Redis (optional object cache)​

Redis is disabled by default (enable_redis = false). It is an optional object cache and is not required for LimeSurvey to run. When redis_host is left empty and enable_nfs is true, the NFS server VM's IP is used as the Redis endpoint.

  • Console: Memorystore → Redis (if using a managed instance).
  • CLI:
    redis-cli -h <redis-host> ping
    # Inspect env injected into the running revision:
    gcloud run services describe <service-name> --region "$REGION" \
    --format='value(spec.template.spec.containers[0].env)'

F. Secret Manager​

The LimeSurvey super-administrator password (ADMIN_PASSWORD) is generated automatically and stored in Secret Manager, then injected as a secret env. The database password is managed separately by the foundation.

  • Console: Security → Secret Manager.
  • CLI:
    gcloud secrets list --project "$PROJECT" --filter="name~admin-password"
    gcloud secrets versions access latest --secret=<secret-name> --project "$PROJECT"

See App_CloudRun for injection and rotation details.

G. Networking & ingress​

The service is reachable at its run.app URL by default, allowing the public access needed for anonymous survey respondents. An external HTTPS load balancer with a custom domain, Cloud CDN, and Cloud Armor can be layered on; ingress settings and VPC egress control connectivity.

  • Console: Cloud Run (service URL); Network services → Load balancing.
  • CLI:
    gcloud run services describe <service-name> --region "$REGION" --format='value(status.url)'
    gcloud compute addresses list --project "$PROJECT"

See App_CloudRun.

H. Cloud Logging & Monitoring​

Container logs flow to Cloud Logging; Cloud Run and Cloud SQL metrics flow to Cloud Monitoring, with optional uptime checks and alert policies.

  • Console: Logging → Logs Explorer; Monitoring → Dashboards / Alerting.
  • CLI:
    gcloud run services logs read <service-name> --project "$PROJECT" --region "$REGION" --limit 50

3. LimeSurvey Application Behaviour​

  • First-deploy database setup. An initialization Job runs db-init.sh using mysql:8.0-debian. It connects over the Cloud SQL socket (if mounted) or the private-IP TCP fallback and idempotently creates the application database and user, grants privileges, and verifies the app user can connect. The job is safe to re-run.
  • Schema created on container start. There is no separate migration job. Once db-init has provisioned an empty database, the upstream martialblog/limesurvey entrypoint runs LimeSurvey's console installer / updatedb on boot to build (or upgrade) the schema. If the container reports healthy but every page 500s with "table settings_global not found", the installer silently failed — almost always a storage-engine problem (see InnoDB note below) or a DB the installer could not reach.
  • InnoDB is forced. DB_MYSQL_ENGINE = InnoDB and DBENGINE = InnoDB are set because Cloud SQL disables MyISAM. Do not override these back to MyISAM — table creation will fail.
  • ADMIN_PASSWORD is required. The container exits 1 without it. It is auto-generated and stored in Secret Manager, and seeds the initial super-admin (admin / admin@techequity.cloud) on first boot. Retrieve it before first login:
    gcloud secrets versions access latest \
    --secret="$(gcloud secrets list --project "$PROJECT" \
    --filter='name~admin-password' --format='value(name)' | head -1)" \
    --project "$PROJECT"
  • Public URL. PUBLIC_URL is set from the predicted service URL at plan time and corrected at runtime from CLOUDRUN_SERVICE_URL, so survey links and static assets resolve on the real Cloud Run host. Confirm the deployed URL:
    gcloud run services describe <service-name> --region "$REGION" \
    --project "$PROJECT" --format='value(status.url)'
  • Health path. The startup probe is TCP against the container port; the liveness probe is GET / (LimeSurvey serves an unauthenticated 200 at the root landing page). Allow generous first-boot time for the console installer.
  • Uploaded files. Persist under /var/www/html/upload via the NFS mount. Without NFS, uploaded assets are lost when the instance is recycled.
  • Inspect job execution:
    gcloud run jobs list --project "$PROJECT" --region "$REGION"
    gcloud run jobs executions list --job <job-name> --project "$PROJECT" --region "$REGION"

4. Configuration Variables​

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

Group 3 — Application Identity​

VariableDefaultDescription
application_namelimesurveyBase name for the service, registry repo, and secrets. Do not change after first deploy.
display_nameLimeSurveyHuman-readable name shown in the Console.
application_versionlatestMaps to the martialblog/limesurvey base tag; latest resolves to the pinned 6-apache. Pin (e.g. 6-apache) in production.

Group 4 — Runtime & Scaling​

VariableDefaultDescription
deploy_applicationtrueSet false to provision infrastructure only.
cpu_limit1000mCPU per instance; 1 vCPU minimum for LimeSurvey + MySQL.
memory_limit2GiMemory per instance; 512Mi minimum, 2Gi recommended.
min_instance_count00 enables scale-to-zero; set 1 to avoid cold starts.
max_instance_count1Keep at 1 unless shared NFS + session handling for multi-instance is confirmed.
container_port8080LimeSurvey (Apache) listens on 8080.
execution_environmentgen2Gen2 required for NFS and GCS Fuse mounts.
timeout_seconds300Max request duration; raise for large CSV imports.
enable_cloudsql_volumefalsefalse uses private-IP TCP to MySQL; set true for the Auth Proxy socket.

Group 5 — Access & Ingress Control​

VariableDefaultDescription
ingress_settingsallall allows anonymous survey respondents. internal blocks the public.
enable_iapfalseRequire Google sign-in. Blocks anonymous respondents.

Group 11 — Storage & Filesystem​

VariableDefaultDescription
enable_nfstrueProvisions Filestore and mounts it to persist /var/www/html/upload. Requires gen2.
nfs_mount_path/var/www/html/uploadContainer mount path for the NFS volume.
create_cloud_storagetrueCreate the declared GCS buckets.
gcs_volumes[]GCS Fuse volume mounts (requires gen2).

Group 12 — Database Backend​

VariableDefaultDescription
database_typeMYSQL_8_0Fixed to MySQL 8.0. Other engines are unsupported.
db_namelimesurveyDatabase name (injected as DB_NAME). Immutable after first deploy.
db_userlimesurveyApplication DB user (injected as DB_USERNAME). Password auto-generated in Secret Manager.

Group 21 — Redis Cache​

VariableDefaultDescription
enable_redisfalseOptional object cache; not required.
redis_host""Redis endpoint. Leave empty to use the NFS server IP (requires enable_nfs = true).
redis_port6379Redis port.

All other inputs follow standard App_CloudRun behaviour.


5. Outputs​

Returned on a successful deployment — the quickest way to locate and explore the running resources.

OutputDescription
service_nameCloud Run service name.
service_urlDefault run.app URL of the service.
service_locationRegion the service runs in.
stage_servicesStage-specific service details (Cloud Deploy).
load_balancer_ip / load_balancer_urlExternal HTTPS load balancer IP / URL (when enabled).
database_instance_nameCloud SQL instance name.
database_name / database_userApplication database name / user.
database_password_secretSecret Manager secret holding the DB password.
database_host / database_portDB endpoint / port.
storage_bucketsCreated Cloud Storage buckets.
network_name / network_exists / regionsVPC network, presence, regions.
container_image / container_registryDeployed image and Artifact Registry repo.
monitoring_enabled / monitoring_notification_channels / uptime_check_namesMonitoring status, channels, uptime checks.
initialization_jobsNames of the setup jobs.
deployment_id / tenant_id / resource_prefixNaming identifiers.
project_id / project_numberProject identifiers.
cicd_enabled / github_repository_url / cicd_configurationCI/CD status and details.
artifact_registry_repository / cloudbuild_trigger_name / cloudbuild_trigger_idRegistry and build trigger.
vpc_sc_enabled / vpc_sc_perimeter_name / vpc_sc_dry_run_modeVPC-SC status.
audit_logging_enabled / artifact_registry_cmek_enabledAudit logging and CMEK status.

6. Configuration Pitfalls & Sensible Defaults​

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

Inherited plan-time validation. This module passes its configuration through the App_CloudRun foundation engine, which validates values and combinations at plan time — a gen1 runtime with NFS/GCS mounts, IAP with no authorized identities, an out-of-range redis_port/backup_retention_days, a database_type that does not match an enabled extension. Invalid configuration fails the plan with a clear, named error before any resource is created, so most mistakes below are caught up front rather than at apply or runtime.

SettingSensible valueRiskConsequence if wrong
DB_MYSQL_ENGINE / DBENGINE (auto InnoDB)Never set to MyISAMCriticalCloud SQL disables MyISAM; the installer's CREATE TABLE … ENGINE=MyISAM fails and every page 500s ("table settings_global not found").
database_typeMYSQL_8_0CriticalLimeSurvey requires MySQL; changing to Postgres/None breaks startup.
db_name / db_userSet onceCriticalImmutable after first deploy; renaming recreates the DB/user and destroys all survey data.
ADMIN_PASSWORD (auto-generated)Retrieve from Secret ManagerCriticalThe container exits 1 without it; changing it re-seeds the super-admin on next boot.
enable_backup_importfalse unless restoringCriticalEnabling without a valid backup URI fails the import job.
enable_nfstrueHighWithout NFS, uploaded assets under /var/www/html/upload are lost when the instance recycles.
max_instance_count1HighMultiple instances without confirmed shared NFS + session handling cause inconsistent upload state.
execution_environmentgen2HighNFS/GCS mounts require gen2; gen1 fails the plan-time validation.
ingress_settingsallHighinternal blocks anonymous survey respondents from reaching public surveys.
enable_iaponly for internal-only surveysHighIAP requires Google sign-in for every request, blocking anonymous respondents.
memory_limit2GiHighBelow 512Mi risks OOM during large survey rendering or CSV import.
enable_cloudsql_volumefalse (TCP)MediumLimeSurvey/MySQL uses private-IP TCP; forcing the socket without a mounted volume can stall the DB connection.
min_instance_count1 for productionMediumScale-to-zero (0) adds cold-start latency on the first request after idle.
application_versionpin (e.g. 6-apache)Mediumlatest resolves to the pinned 6-apache; an unpinned major bump can require a schema upgrade.

For the foundation behaviour referenced throughout — service identity, scaling and concurrency, ingress and load balancing, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC-SC, backups, and image mirroring — see App_CloudRun. LimeSurvey-specific application configuration shared with the GKE variant is described in LimeSurvey_Common.

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