Ghost on Google Cloud Run

Ghost is a modern open-source publishing platform powering 2M+ publications with built-in membership, subscriptions, and newsletters. This module deploys Ghost 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 Ghost 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

Ghost runs as a Node.js 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	Node.js service, 1 vCPU / 512 MiB by default, request-based billing with scale-to-zero
Database	Cloud SQL for MySQL 8.0	Required — Ghost 6.x does not support PostgreSQL
Shared files	Filestore (NFS)	Uploaded content and themes shared across all instances (gen2 required)
Object storage	Cloud Storage	A dedicated content bucket (ghost-content) provisioned automatically
Cache	Redis	Enabled by default; falls back to the NFS host IP when no Redis host is given
Secrets	Secret Manager	Database password managed automatically
Ingress	Cloud Run URL / Cloud Load Balancing	Default run.app URL, optional external HTTPS load balancer + custom domain

Sensible defaults worth knowing up front:

• MySQL 8.0 is mandatory. Ghost 6.x requires MySQL; PostgreSQL is not supported and will not start.
• database__client = "mysql" is injected automatically. Without this Ghost silently falls back to SQLite — the module handles it so you never need to set it manually.
• Redis is enabled by default. Ghost uses Redis for page caching to reduce database load and improve response times.
• Dynamic URL detection. The custom entrypoint queries the Cloud Run API at startup to discover the service URL and export it as url for Ghost. An explicit url environment variable takes precedence.
• A ghost-content GCS bucket is provisioned automatically by Ghost_Common and does not need to be added to storage_buckets.
• A db-init job runs on every apply to idempotently create the Ghost MySQL database and user.
• Health probes target / with a 90-second initial delay to allow Ghost to run database migrations and compile themes on first boot.
• The database password is generated automatically and stored in Secret Manager.

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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 Ghost service

Ghost 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

Ghost stores all application data (posts, members, settings) in a managed Cloud SQL for MySQL 8.0 instance. The service connects privately through the Cloud SQL Auth Proxy over a Unix socket (no public IP). On first deploy a db-init Job creates the application database and user.

• 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> --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. Filestore (NFS) and Cloud Storage

Uploaded content (images, themes, files) is written to a Filestore (NFS) share mounted into the service so all instances share the same files. A dedicated Cloud Storage bucket (ghost-content) is also provisioned automatically for content. The gen2 execution environment is required for NFS mounts.

• Console: Filestore → Instances; Cloud Storage → Buckets.
• CLI:

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

See App_CloudRun for the NFS mount, GCS Fuse, and CMEK.

D. Redis cache

Redis backs Ghost's page caching. When no external Redis host is configured and NFS is enabled, the NFS host IP is used as the Redis endpoint.

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

  redis-cli -h <redis-host> ping
  redis-cli -h <redis-host> info keyspace

E. Secret Manager

The database password is stored in Secret Manager and injected into the service at runtime; plaintext never appears in configuration.

• Console: Security → Secret Manager.
• CLI:

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

See App_CloudRun for injection and rotation details.

F. Networking & ingress

The service is reachable at its run.app URL by default. 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.

G. 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

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3. Ghost Application Behaviour

• First-deploy database setup. A db-init Job connects to Cloud SQL via the Auth Proxy and idempotently creates the Ghost database (with utf8mb4 charset and utf8mb4_0900_ai_ci collation), creates the application user, and grants full privileges. The job runs on every apply and is safe to re-run.
• Slow first boot. Ghost runs database migrations and compiles themes on first start. The startup probe allows 90 seconds of initial delay — do not reduce this below 60 seconds or the instance will be killed before Ghost finishes initialising.
• Dynamic URL detection. On startup the custom entrypoint queries the Cloud Run metadata API to discover the service URL and sets it as Ghost's url and admin__url. An explicit url environment variable always takes precedence. This ensures Ghost generates correct absolute links in membership emails and admin navigation.
• Database connection. The entrypoint maps DB_HOST, DB_USER, DB_NAME, DB_PASSWORD, and DB_PORT to Ghost's database__connection__* settings automatically. When DB_HOST starts with / it is treated as a Unix socket path (the Cloud SQL Auth Proxy socket).
• SMTP for email. Ghost requires SMTP for member sign-ups, password resets, and newsletter delivery. Pre-populated environment_variables (SMTP_HOST, SMTP_PORT, SMTP_USER, SMTP_PASSWORD, SMTP_SSL, EMAIL_FROM) — configure them before inviting members.
• Admin login. Ghost's admin panel is at <url>/ghost. On first boot Ghost creates an admin user interactively.
• Health path. Startup and liveness probes target /, which returns HTTP 200 when Ghost is fully initialised.

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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 Ghost are listed; every other input is inherited from App_CloudRun with its standard behaviour.

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.

Group 3 — Application Identity

Variable	Default	Description
application_name	ghost	Base name for resources. Do not change after first deploy.
display_name	Ghost Publishing	Friendly name shown in the Console.
description	Ghost - Professional publishing platform	Service description.
application_version	6.14.0	Ghost image version tag; increment to trigger a new revision.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
cpu_limit	1000m	CPU per instance; sized for light/typical usage — raise to 2000m for production with heavy image processing or membership.
memory_limit	512Mi	Memory per instance (Ghost's floor); raise to 1Gi+ for production with active membership features.
min_instance_count	0	Minimum instances; 0 enables scale-to-zero — set 1 to avoid cold starts with migration delays.
container_port	2368	Ghost's native HTTP port.
container_image_source	custom	custom builds via Cloud Build (default); prebuilt deploys an existing image.
enable_cloudsql_volume	true	Cloud SQL Auth Proxy for socket connections. Required for Ghost.
execution_environment	gen2	Cloud Run gen2 required for NFS mounts.
traffic_split	[]	Split traffic across revisions for staged rollouts.
max_revisions_to_retain	7	How many old revisions to keep.

Group 5 — Access & Ingress Control

Variable	Default	Description
enable_iap	false	Require Google sign-in via Identity-Aware Proxy.
iap_authorized_users / iap_authorized_groups	[]	Who may access through IAP.
ingress_settings	all	Which networks may reach the service (all / internal / LB-only).
vpc_egress_setting	PRIVATE_RANGES_ONLY	How outbound traffic is routed through the VPC connector.

Group 6 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{SMTP_HOST="", SMTP_PORT="587", SMTP_USER="", SMTP_PASSWORD="", SMTP_SSL="false", EMAIL_FROM="ghost@example.com"}	SMTP settings pre-populated for Ghost email delivery (use port 587 STARTTLS or 465 SSL — Google Cloud blocks outbound port 25). database__client=mysql is injected automatically.
secret_environment_variables	{}	Map of env var → Secret Manager secret name.
secret_propagation_delay	30	Replication wait after secret creation.
secret_rotation_period	2592000s	Rotation notification frequency.

Group 7 — Backup & Restore

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

Group 8 — CI/CD & Binary Authorization

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

Group 9 — Custom SQL

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_CloudRun.

Group 10 — Domain, CDN, Cloud Armor & Image Retention

Variable	Default	Description
application_domains	[]	Custom hostnames for the external load balancer. Ghost must know its public URL — ensure the domain matches.
enable_cdn	false	Enable Cloud CDN on the LB backend.
enable_cloud_armor / admin_ip_ranges	off	Attach a WAF policy / restrict privileged access.
max_images_to_retain / delete_untagged_images / image_retention_days	(set)	Artifact Registry cleanup policy.

Group 11 — Storage & Filesystem

Variable	Default	Description
enable_nfs	true	Shared Filestore volume for Ghost content. Requires gen2.
nfs_mount_path	/mnt/nfs	Mount path inside the container.
create_cloud_storage / storage_buckets / gcs_volumes	(set)	Additional buckets / GCS Fuse mounts. The ghost-content bucket is always provisioned automatically.
manage_storage_kms_iam / enable_artifact_registry_cmek	false	CMEK options.

Group 12 — Database Backend

Variable	Default	Description
database_type	MYSQL_8_0	Ghost requires MySQL 8.0 — do not change.
db_name	ghost	MySQL database name. Immutable after first deploy.
db_user	ghost	Application user. Immutable after first deploy.
database_password_length	32	Generated password length (16–64).
enable_auto_password_rotation / rotation_propagation_delay_sec	off	DB password rotation.
db_host_env_var_name / db_name_env_var_name / db_user_env_var_name / db_port_env_var_name / service_url_env_var_name	""	Additional env var names for connection details.

Group 13 — Jobs & Scheduled Tasks

Variable	Default	Description
initialization_jobs	[]	Leave empty to use the built-in db-init job (mysql:8.0-debian).
cron_jobs	[]	Recurring jobs triggered by Cloud Scheduler.

Group 14 — Observability & Health

Variable	Default	Description
startup_probe	HTTP / 90s initial delay, 10 failures	HTTP startup probe against Ghost's root path. Generous delay for first-boot migrations.
liveness_probe	HTTP / 60s initial delay	Liveness probe targeting Ghost's root path.
uptime_check_config	disabled, path /	Cloud Monitoring uptime check; disabled by default.
alert_policies	[]	Metric alert policies.

Group 21 — Redis Cache

Variable	Default	Description
enable_redis	true	Use Redis for Ghost page caching.
redis_host	""	Redis endpoint. Leave empty to use the NFS host IP.
redis_port	6379	Redis port.
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

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

Output	Description
service_name	Cloud Run service name.
service_url	Default run.app URL of the service.
service_location	Region the service runs in.
stage_services	Stage-specific service URLs (Cloud Deploy).
load_balancer_ip / load_balancer_url	External HTTPS load balancer IP / URL (when enabled).
database_instance_name	Cloud SQL instance name.
database_name / database_user	Application database name / user.
database_password_secret	Secret Manager secret holding the DB password.
database_host / database_port	DB endpoint / port.
storage_buckets	Created Cloud Storage buckets (includes the ghost-content bucket).
network_name / network_exists / regions	VPC network, presence, regions.
container_image / container_registry	Deployed image and Artifact Registry repo.
monitoring_enabled / monitoring_notification_channels / uptime_check_names	Monitoring status, channels, uptime checks.
initialization_jobs	Names of the setup jobs.
deployment_id / tenant_id / resource_prefix	Naming identifiers.
project_id / project_number	Project identifiers.
cicd_enabled / github_repository_url / github_repository_owner / github_repository_name / cicd_configuration	CI/CD status and details.
artifact_registry_repository / cloudbuild_trigger_name / cloudbuild_trigger_id	Registry and build trigger.
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	MYSQL_8_0	Critical	Ghost requires MySQL 8.0; any other engine breaks startup.
db_name / db_user	set once	Critical	Immutable after first deploy; renaming recreates the DB/user and destroys all data.
enable_nfs	true	Critical	Without shared storage, uploaded content is lost between instances/restarts.
container_port	2368	Critical	Ghost's native port; mismatching it causes all health probes to fail.
enable_backup_import	false unless restoring	Critical	Enabling without a valid backup_uri fails the import job.
startup_probe initial_delay_seconds	90	High	Reducing below 60 causes Cloud Run to kill Ghost before it finishes running migrations.
enable_redis	true	High	Without Redis, Ghost serves all pages without a cache, increasing database load.
redis_host	"" (NFS) or explicit	High	No valid endpoint if Redis is on but NFS is off and no host is set.
memory_limit	512Mi+	High	Too little memory causes Node.js OOM during newsletter sends or theme compilation; raise beyond the 512Mi default for active membership/newsletter use.
environment_variables SMTP settings	real SMTP server	High	No email delivery means no member sign-ups, no password resets, no newsletters.
container_image_source	custom	High	The upstream Ghost image lacks the custom entrypoint that maps DB credentials and detects the service URL.
execution_environment	gen2	High	NFS mounts require gen2; gen1 cannot mount Filestore.
min_instance_count	0 (default) or 1	Medium	0 (the default) causes cold starts during which Ghost runs migrations — set 1 if first-request timeouts matter.
enable_iap / enable_cloud_armor	enable for admin-facing	Medium	The Ghost admin panel (/ghost) is otherwise publicly reachable.
backup_retention_days	7 (raise for prod)	Medium	Too short for compliance retention.

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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. Ghost-specific application configuration shared with the GKE variant is described in Ghost_Common.