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Certification track: Associate Cloud Engineer (ACE) · Professional Cloud Developer (PCD)

WordPress on GKE Autopilot

WordPress on GKE Autopilot

WordPress is the world's most popular content management system, powering over 43% of all websites globally. This module deploys WordPress on GKE Autopilot on top of the App_GKE foundation, which provisions and manages the shared Google Cloud and Kubernetes infrastructure.

This guide focuses on the cloud services WordPress uses and how to explore and operate them from the Google Cloud Console and the command line. For the mechanics that are common to every GKE application — Workload Identity, ingress, autoscaling, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC Service Controls, backups, and the deployment lifecycle — refer to the App_GKE foundation guide rather than repeating them here.


What WordPress costs on RAD, and how that compares​

Running WordPress on GKE Autopilot pods in your own Google Cloud project costs about $110.13/month in Google Cloud charges, on top of a one-off 175-credit RAD module fee charged once at deploy time. WordPress needs a MySQL database and a shared NFS/cache file server for uploads and sessions, which together are most of the $110.13 above. In a RAD-managed project the module fee drops to 157.5 credits (10% lower) and the running cost is metered hourly in credits instead of billed directly by Google — see Pause it for free below for the one RAD-managed advantage a self-hosted VPS cannot match — or see the Cloud Run guide for the lower-cost option.

What you pay on RAD​

Own projectRAD-managed project
Module fee (one-off)175 credits157.5 credits (10% lower)
Build time~3-6 credits per build, either way~3-6 credits per build, either way
Google Cloud running cost$110.13/month, billed by Google at list price~99 credits/day, metered at list price plus RAD's margin

Default running cost in your own project

ResourceUS$/month (Google list price, us-central1)
GKE Autopilot pod, 1x vCPU / 2 GiB$39.68
Cloud SQL for MySQL, 1 vCPU / 3.75 GB, zonal, 10 GB SSD$51.02
NFS/cache file server (small VM)$13.43
Cloud NAT and networking$5.00
Cloud Storage (add-ons, backups)$1.00
GKE cluster management feeshared across every GKE app in the project; $0 if this is your only cluster, else ~73
Total$110.13

The GKE cluster management fee is excluded from the total above because it is shared across every GKE app in the project — $0 if this is the only one, otherwise roughly $73/month split across however many you run.

How it compares​

  • WordPress.com, run by Automattic, is the official hosted version of the same software: its pricing page (checked 8 October 2026) lists Personal at $4/mo, Premium at $8/mo, Business at $25/mo and Commerce at $45/mo on monthly billing (cheaper on annual terms) — all under RAD's $110.13/month running cost, but on a shared multi-tenant platform with plugin/theme restrictions below the Business tier.
  • RAD's module instead gives you a dedicated Cloud Run service, your own Cloud SQL database and full plugin/theme freedom from the start, which is what the extra cost above WordPress.com buys.
  • A bare-VPS alternative also works: a DigitalOcean or Hetzner 2 vCPU/4GB box at about $24/mo, or a GCP Compute Engine e2-standard-2 at about $49/mo, can self-host WordPress and MySQL together — cheaper than either RAD or WordPress.com in cash terms, with none of the managed backups, patching or monitoring either provides.

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

This is the headline advantage of a RAD-managed project, and it costs nothing while paused. Deleting a RAD-managed project unlinks its billing first, then asks Google to delete the project outright — Google's own 30-day recoverable soft delete. Unlike deleting one module, this does not tear down Cloud SQL, any VM, or the compute resource one by one: the whole project simply stops, and nothing is charged while it waits, because billing is already unlinked.

Restoring, within 30 days and only by the project's owner, 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. This costs only a handful of credits (under US$1) in total for a typical 2-3-deployment chain.

What this needs: you must own the project (not one RAD only manages billing for), you must restore it yourself within 30 days — after that Google deletes it for good — and restoring is admitted like creating a new project, so your purchased credit balance must still clear the tier's floor (100 credits for the sandbox tier most study/demo use fits). Google says most services are fully working again within 36 hours of a restore.

One real gap: nightly backups are written to a bucket inside the project, and that bucket has Cloud Storage's soft-delete explicitly turned off, 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 WordPress and want to keep that work, copy a backup out (to Google Drive, or a bucket outside the project) before deleting. For a default install with nothing irreplaceable in it, this does not matter.

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

In your own project, or once 30 days have passed on a RAD-managed one, there is no free pause — deleting removes the resources for good, and bringing WordPress back means redeploying from scratch. That costs about 178-181 credits (the 175-credit module fee plus a build).

Deleting only saves money once WordPress would otherwise sit unused long enough to clear that redeploy cost against its own running cost — for WordPress, that's about 5 days or more. Most of this running cost is usually the database and any shared file/cache VM — those stop only once nothing else in the project uses them, so deleting this app while something else shares the project saves only its own compute share.

Keep 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 session for a class. Each participant gets the app in their own Google Cloud project for 15 minutes to 24 hours, within an allowance the trainer sets. Either the trainer funds every place, 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 the app 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 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 Billing Catalog API list prices; radmodules.dev/pricing for RAD's own fees and daily-credit estimates; Google's project delete/restore documentation for the pause/restore claims. WordPress.com plan prices from wordpress.com/pricing, checked 8 October 2026.

1. Overview​

WordPress runs as a PHP/Apache web workload. The deployment wires together a focused set of Google Cloud services:

CapabilityGoogle Cloud serviceNotes
ComputeGKE AutopilotPHP/Apache pods, 1 vCPU / 2 GiB by default, horizontally autoscaled
DatabaseCloud SQL for MySQL 8.0Required — WordPress does not support PostgreSQL
Shared filesFilestore (NFS)wp-content directory (uploads, plugins, themes) shared across all replicas
Object storageCloud StorageA dedicated wp-uploads media bucket
CacheRedisOptional object cache; enabled by default to reduce database load
SecretsSecret ManagerAuto-generated database password and eight WordPress authentication keys and salts
IngressCloud Load BalancingExternal LoadBalancer, optional custom domain + managed certificate

Sensible defaults worth knowing up front:

  • MySQL 8.0 is mandatory. The database engine is fixed; selecting PostgreSQL or NONE breaks startup.
  • NFS is required for a functional site. WordPress stores uploaded media, installed plugins, and active themes under wp-content/. Without a shared NFS volume, each pod has an isolated and ephemeral wp-content — plugins are lost on restart and replicas serve different versions of the site.
  • Eight WordPress authentication keys and salts are auto-generated and stored in Secret Manager; you never set them in plain text.
  • Redis object cache is enabled by default. Reduces database load by caching the results of expensive queries. Requires a Redis host to be reachable (defaults to the NFS server IP when redis_host is left empty).
  • Session affinity is ClientIP. WordPress uses PHP sessions for the admin panel; requests from a browser must be pinned to one pod.
  • The startup probe is TCP, not HTTP. WordPress may not yet respond to HTTP requests during database initialisation on first boot; a TCP probe only checks that Apache's port is open.

2. Google Cloud Services & How to Explore Them​

All commands assume you have run gcloud container clusters get-credentials <cluster> --region <region> --project <project> and that PROJECT, REGION, and NAMESPACE are set. The namespace and other identifiers are reported in the deployment Outputs.

A. GKE Autopilot — the WordPress workload​

WordPress pods are scheduled on Autopilot, which bills for the CPU/memory the pods actually request. Horizontal Pod Autoscaling sizes the deployment between the minimum and maximum replica counts.

  • Console: Kubernetes Engine → Workloads → select the WordPress workload to see pods, revisions, and events. Kubernetes Engine → Services & Ingress shows the external IP.
  • CLI:
    kubectl get pods,svc,hpa -n "$NAMESPACE"
    kubectl logs -n "$NAMESPACE" deploy/<service-name> --tail=100
    kubectl describe hpa -n "$NAMESPACE" # current vs target utilisation

See App_GKE for how Autopilot, scaling, and the workload type (Deployment vs StatefulSet) are managed.

B. Cloud SQL for MySQL 8.0​

WordPress stores all site data (posts, users, settings, comments) in a managed Cloud SQL for MySQL 8.0 instance. Pods reach it privately through the Cloud SQL Auth Proxy sidecar over a Unix socket, so no public IP is exposed. On first deploy an initialisation Job creates the application database and user.

  • 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> --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_GKE.

C. Filestore (NFS) and Cloud Storage​

WordPress's wp-content directory is mapped onto a Filestore (NFS) share mounted into every pod so all replicas share the same plugins, themes, and uploaded media. A dedicated Cloud Storage bucket (wp-uploads) is also provisioned for media assets; the workload service account is granted access automatically.

  • Console: Filestore → Instances for the NFS share; Cloud Storage → Buckets for the media bucket.
  • CLI:
    gcloud filestore instances list --project "$PROJECT"
    gcloud storage buckets list --project "$PROJECT"
    gcloud storage ls gs://<media-bucket>/ # bucket name is in the Outputs
    # Confirm the NFS share is mounted inside a pod:
    kubectl exec -n "$NAMESPACE" deploy/<service-name> -- df -h | grep -i nfs
    # Confirm PHP limits (useful for diagnosing upload failures):
    kubectl exec -n "$NAMESPACE" deploy/<service-name> -- php -r "
    echo 'memory_limit: ' . ini_get('memory_limit') . PHP_EOL;
    echo 'upload_max_filesize: ' . ini_get('upload_max_filesize') . PHP_EOL;
    echo 'post_max_size: ' . ini_get('post_max_size') . PHP_EOL;
    "

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

D. Redis object cache​

Redis backs WordPress's object cache via the WP Redis plugin, storing the results of expensive database queries in memory and dramatically reducing page load times and database load on busy sites. When redis_host is left empty and NFS is enabled, the NFS server IP is used as the Redis endpoint (the default shared deployment model).

  • 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
    # From inside a WordPress pod:
    kubectl exec -n "$NAMESPACE" deploy/<service-name> -- \
    sh -c 'redis-cli -h $WP_REDIS_HOST -p $WP_REDIS_PORT ping'

E. Secret Manager​

The WordPress database password and the eight WordPress authentication keys and salts are stored as Secret Manager secrets and injected into pods at runtime; plaintext values never appear in configuration or Terraform state.

  • Console: Security → Secret Manager.
  • CLI:
    gcloud secrets list --project "$PROJECT"
    # List all secrets belonging to this deployment:
    gcloud secrets list --project "$PROJECT" --filter="name~<resource-prefix>"
    gcloud secrets versions access latest --secret=<secret-name> --project "$PROJECT"

The database password secret name is in the Outputs. See App_GKE for the Secret Store CSI integration and rotation.

F. Networking & ingress​

By default the workload is exposed through an external Cloud Load Balancing IP. A custom domain with a Google-managed certificate can be enabled, and a static IP can be reserved so the address survives redeploys.

  • Console: Network services → Load balancing; VPC network → IP addresses.
  • CLI:
    kubectl get ingress,svc -n "$NAMESPACE"
    gcloud compute addresses list --project "$PROJECT"

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

G. Cloud Logging & Monitoring​

Pod stdout/stderr flow to Cloud Logging; GKE 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="k8s_container" AND resource.labels.namespace_name="'"$NAMESPACE"'"' \
    --project "$PROJECT" --limit 50

3. WordPress Application Behaviour​

  • First-deploy database setup. An initialisation Job using the mysql:8.0-debian image creates the WordPress database and user and grants privileges before the application starts. It runs on every tofu apply because it is idempotent — it safely skips steps that are already complete.

  • Authentication keys and salts. Eight 64-character WordPress security secrets (auth key, secure auth key, logged-in key, nonce key, and their corresponding salts) are generated automatically on first deploy and stored in Secret Manager. Rotating these secrets immediately invalidates all active browser sessions — every logged-in user will be signed out.

  • PHP configuration baked at build time. php_memory_limit, upload_max_filesize, and post_max_size are applied to the container image at Cloud Build time. Changing them triggers a new image build and rolling update.

  • WordPress table prefix. WORDPRESS_TABLE_PREFIX is set to wp_ automatically. Override via environment_variables only when migrating an existing database with a non-standard prefix.

  • Probe behaviour. The startup probe uses TCP (port open check) rather than HTTP to avoid failures during WordPress's database initialisation phase. The liveness probe polls /wp-admin/install.php — which returns HTTP 200 whether WordPress is freshly installed or already configured — with a 300-second initial delay to allow the db-init job to complete. Do not reduce failure_threshold below 10 for the startup probe on production deployments.

  • WP_HOME and WP_SITEURL. Both constants are set at runtime from the platform-injected GKE_SERVICE_URL, so they take precedence over the siteurl/home rows WordPress stored at install time. If the Gateway address changes, the site follows it instead of redirecting to a stale host.

  • Scheduled tasks. WordPress's built-in wp-cron pseudo-cron relies on site traffic to trigger. For production sites with consistent uptime requirements, disable wp-cron in wp-config.php and schedule wp cron event run --due-now as a cron_jobs entry.

    Inspect scheduled tasks:

    kubectl get cronjobs -n "$NAMESPACE"
    kubectl get jobs -n "$NAMESPACE" --sort-by=.metadata.creationTimestamp

4. Configuration Variables​

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

Group 1 — Project & Identity​

VariableDefaultDescription
project_id(required)Target Google Cloud project.
regionus-central1Region for the workload and regional resources.

Group 2 — Deployment Environment​

VariableDefaultDescription
tenant_iddemoShort 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​

VariableDefaultDescription
application_namewordpressBase name for resources. Do not change after first deploy.
application_display_nameWordpressFriendly name shown in the Console.
application_descriptionWordpress CMS on GKEWorkload description annotation.
application_versionlatestWordPress image version tag passed as APP_VERSION build argument. Use a pinned version (e.g. 6.7.1) in production for reproducible builds.
php_memory_limit512MPHP memory_limit baked into the container image at build time. Increase for heavy plugin workloads (e.g. WooCommerce, Elementor).
upload_max_filesize64MMaximum size of a single file upload. Must be ≤ post_max_size.
post_max_size64MMaximum size of all POST data in a single HTTP request. Must be ≥ upload_max_filesize.

Group 4 — Runtime & Scaling​

VariableDefaultDescription
deploy_applicationtrueSet false to provision infrastructure only.
cpu_limit1000mCPU per pod; 1 vCPU is sufficient for typical sites.
memory_limit2GiMemory per pod; 2 GiB recommended for WordPress with plugins.
min_instance_count1Minimum replicas. Keep ≥ 1 to avoid cold-start latency.
max_instance_count1Maximum replicas. Increase only after verifying all installed plugins handle concurrent pod access correctly.
container_port80WordPress/Apache listens on port 80.
enable_cloudsql_volumetrueCloud SQL Auth Proxy sidecar for socket connections. Required.
enable_vertical_pod_autoscalingfalseLet Autopilot tune resource requests automatically.

Group 5 — Environment Variables & Secrets​

VariableDefaultDescription
environment_variables{}Extra non-secret settings. WORDPRESS_TABLE_PREFIX, WORDPRESS_DEBUG, and Redis vars are set automatically.
secret_environment_variables{}Map of env var → Secret Manager secret name. Eight WordPress auth secrets are injected automatically.

Group 6 — GKE Backend & Cluster​

VariableDefaultDescription
service_typeLoadBalancerHow the Service is exposed.
session_affinityClientIPSticky routing required for WordPress PHP sessions in the admin panel.
workload_typenullAuto-resolves to StatefulSet when per-pod storage is enabled.
network_tags['nfsserver']Node/pod tags; nfsserver is required for NFS connectivity.

Group 7 — StatefulSet​

VariableDefaultDescription
stateful_pvc_enablednullEnable per-pod PVCs when using StatefulSet.
stateful_pvc_size10GiStorage size per PVC. WordPress media libraries grow quickly — plan for 50–200 GiB on active sites.
stateful_pvc_mount_path/dataContainer path for the per-pod PVC.
stateful_pvc_storage_classstandard-rwoKubernetes StorageClass for PVCs.

Group 8 — Resource Quota​

VariableDefaultDescription
enable_resource_quotafalseCap namespace CPU/memory/object counts.
quota_memory_requests / quota_memory_limits""Must use binary units (4Gi, 8192Mi) — bare integers are read as bytes and block all scheduling.

Group 9 — Reliability Policies​

VariableDefaultDescription
enable_pod_disruption_budgetfalseProtect availability during node upgrades. The default is false because the default max_instance_count is 1; enable only when running multiple replicas.
pdb_min_available1Raise min_instance_count above 1 to leave eviction headroom.
enable_topology_spreadfalseSpread pods across zones for multi-replica deployments.

Group 10 — Observability & Health​

VariableDefaultDescription
startup_probeTCP, 30s delay, threshold 20TCP probe on port 80 — avoids HTTP failures during database initialisation on first boot. Do not reduce failure_threshold below 10.
liveness_probeHTTP /wp-admin/install.php, 300s delayHTTP probe; 300-second initial delay accommodates the db-init job.
uptime_check_configdisabledOptional Cloud Monitoring uptime check.
alert_policies[]Optional metric alert policies.

Group 11 — Jobs & Scheduled Tasks​

VariableDefaultDescription
initialization_jobs[]Leave empty to use the built-in db-init job. Supplying a non-empty list replaces the default entirely.
cron_jobs[]Recurring scheduled tasks. Use to replace wp-cron with a dedicated schedule for reliable WordPress cron execution.

Group 12 — CI/CD & GitHub Integration​

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

Group 13 — Filesystem (NFS)​

VariableDefaultDescription
enable_nfstrueShared Filestore volume for WordPress wp-content (keep enabled).
nfs_mount_path/var/www/html/wp-contentMount path inside the container. The startup script symlinks wp-content here.

Group 14 — Cloud Storage & Artifact Registry​

VariableDefaultDescription
create_cloud_storagetrueProvision the wp-uploads media bucket.
storage_buckets[{name_suffix="data"}]Additional buckets.
gcs_volumes[]GCS Fuse mounts.
manage_storage_kms_iam / enable_artifact_registry_cmekfalseCMEK options.

Group 15 — Redis Cache​

VariableDefaultDescription
enable_redistrueUse Redis for WordPress object caching.
redis_host""Leave empty to use the NFS server IP (default shared model); set explicitly for a dedicated Memorystore instance.
redis_port6379Redis port.
redis_auth""Optional Redis auth password (sensitive).

Group 16 — Database Backend​

VariableDefaultDescription
database_typenull (resolved to MYSQL_8_0 by Wordpress_Common)Fixed — do not change. WordPress requires MySQL.
application_database_namewpDatabase name. Immutable after first deploy.
application_database_userwpApplication user. Immutable after first deploy.
database_password_length32Generated password length (16–64).
enable_auto_password_rotationfalseZero-downtime DB password rotation.

Group 17 — Backup & Maintenance​

VariableDefaultDescription
backup_schedule0 2 * * *Automated backup cron (UTC).
backup_retention_days7Retention; raise to 30–90 for production/compliance.
enable_backup_import / backup_source / backup_file / backup_formatrestore optionsRestore from a backup on deploy. Note: this module uses backup_file (filename within the GCS backup bucket), not backup_uri.

Group 18 — 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. See App_GKE.

Group 19 — Custom Domain, Static IP & Networking​

VariableDefaultDescription
enable_custom_domaintrueProvision Ingress for custom hostnames + managed certificate.
application_domains[]Hostnames to serve.
reserve_static_iptrueStable external IP across redeploys.

Group 20 — Identity-Aware Proxy (IAP)​

VariableDefaultDescription
enable_iapfalseRequire Google sign-in in front of WordPress.
iap_authorized_users / iap_authorized_groups[]Who may access.
iap_oauth_client_id / iap_oauth_client_secret""Required when IAP is enabled (sensitive).
iap_support_email""Shown on the OAuth consent screen.

Group 21 — Cloud Armor​

VariableDefaultDescription
enable_cloud_armorfalseAttach a Cloud Armor (WAF) policy to the Ingress backend. Strongly recommended — WordPress login pages are prime targets for brute-force attacks.
admin_ip_ranges[]CIDRs allowed privileged access.
cloud_armor_policy_namedefault-waf-policyPolicy name.

Group 22 — VPC Service Controls & Audit Logging​

VariableDefaultDescription
enable_vpc_scfalseEnforce a VPC-SC perimeter (requires organization_id).
vpc_cidr_ranges / vpc_sc_dry_run(set)Access level CIDRs / dry-run mode.
enable_audit_loggingfalseDetailed Cloud Audit Logs.

5. Outputs​

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

OutputDescription
service_nameKubernetes Service name.
namespaceNamespace the workload runs in.
service_cluster_ipIn-cluster ClusterIP.
stage_service_cluster_ipsMap of ClusterIPs for Cloud Deploy stage services.
service_external_ipExternal LoadBalancer IP (when a static IP is reserved).
service_urlURL to reach WordPress.
database_instance_nameCloud SQL instance name.
database_nameApplication database name.
database_userApplication database user.
database_password_secretSecret Manager secret holding the DB password.
database_host / database_portDB endpoint (127.0.0.1 via the Auth Proxy) / port.
storage_bucketsCreated Cloud Storage buckets.
network_name / network_exists / regionsVPC network, presence, available regions.
container_image / container_registryDeployed image and Artifact Registry repo.
monitoring_enabled / monitoring_notification_channelsMonitoring status and channels.
initialization_jobs / db_import_jobNames of the setup and (optional) import jobs.
deployment_id / tenant_id / resource_prefixNaming identifiers.
project_id / project_numberProject identifiers.
cicd_enabled / github_repository_url / github_repository_owner / github_repository_name / cicd_configurationCI/CD status and details.
artifact_registry_repository / cloudbuild_trigger_name / cloudbuild_trigger_idRegistry and build trigger.
kubernetes_readyWhether the cluster/workload is ready. On a first apply of a new inline cluster this is false — run apply a second time to complete the deployment.
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).

SettingSensible valueRiskConsequence if wrong
database_typeMYSQL_8_0 (auto-set)CriticalWordPress requires MySQL; PostgreSQL/NONE breaks startup.
enable_nfstrueCriticalWithout shared storage, plugins/themes/uploads are isolated per pod and lost on restart; multi-replica deployments serve inconsistent site versions.
application_database_name / _userset onceCriticalImmutable after first deploy; renaming recreates the DB/user and destroys all WordPress data.
enable_backup_importfalse unless restoringCriticalEnabling without a valid backup_file in the GCS bucket fails the import job.
quota_memory_requests / _limitsbinary unitsCriticalBare integers are bytes and block all scheduling.
container_image_sourcecustomHighThe custom WordPress image wires the NFS symlink and Cloud SQL socket. Using prebuilt with the vanilla WordPress image breaks Cloud SQL socket connectivity.
nfs_mount_path/mnt/nfs (do not change after deploy)HighThe startup script symlinks wp-content to this path; changing it after initial deployment breaks the symlink.
memory_limit2GiHighWordPress with popular plugins (WooCommerce, Elementor) requires at least 2 GiB; insufficient memory causes PHP fatal errors.
session_affinityClientIPHighWithout stickiness, admin users are logged out on every request that lands on a different pod.
enable_redistrueMediumWith multiple replicas, isolated per-pod in-memory caches cause redundant database queries.
redis_host"" (NFS IP) or explicitHighNo valid Redis endpoint if Redis is on, NFS is off, and no host is set.
enable_cloud_armorenable for public sitesHighWordPress login pages (/wp-login.php, xmlrpc.php) are prime brute-force targets.
php_memory_limit512MMediumMust be within memory_limit; too low causes plugin activation failures and white screens of death.
min_instance_count1Medium0 causes 30–60 second cold starts and potential visible errors for the first visitor after idle.
backup_retention_days7 (raise for prod)MediumToo short for e-commerce or content-heavy sites; one week of posts/orders lost.
stateful_pvc_size10Gi (raise for prod)MediumWordPress media libraries grow quickly; plan for 50–200 GiB for active sites.
enable_network_segmentationenable for shared clustersMediumWithout NetworkPolicy, any pod in the cluster can reach WordPress pods directly.
pdb_min_available vs min_instance_countleave headroomMedium1/1 can stall node upgrades (single pod cannot be evicted).

For the foundation behaviour referenced throughout — IAM and Workload Identity, autoscaling, ingress and certificates, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC-SC, backups, and image mirroring — see App_GKE. WordPress-specific application configuration shared with the Cloud Run variant is described in Wordpress_Common.

Need RAD to do something it does not do yet? Request it on the roadmap, or vote on what is already there.