Metabase on GKE Autopilot

Metabase is an open-source business intelligence and analytics platform that lets non-technical users query, visualise, and share data without writing SQL. This module deploys Metabase 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 Metabase 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.

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1. Overview

Metabase runs as a Java/JVM (Jetty) web workload. The deployment wires together a focused set of Google Cloud services:

Capability	Google Cloud service	Notes
Compute	GKE Autopilot	JVM pods, 2 vCPU / 4 GiB by default, horizontally autoscaled
Database	Cloud SQL for PostgreSQL 15	Required — Metabase stores all application state (questions, dashboards, users) in PostgreSQL
Secrets	Secret Manager	Auto-generated database password; no admin password is managed here (Metabase handles its own)
Ingress	Cloud Load Balancing	External LoadBalancer with a zero-config <ip>.nip.io HTTPS hostname by default (enable_custom_domain = true); set application_domains for a real custom domain

Sensible defaults worth knowing up front:

• PostgreSQL 15 is the only supported engine. All application state — questions, dashboards, collections, users — lives in this database.
• No Redis is required. Metabase does not use Redis for caching; enable_redis defaults to false.
• Session affinity is ClientIP. Sticky routing keeps a browser session on one pod, avoiding session loss during HPA scale-out.
• JVM startup takes 60–120 seconds. The startup probe targets /api/health with a 60-second initial delay and 18 retries, giving ~240 seconds total tolerance. min_instance_count = 1 keeps at least one pod warm.
• MB_JETTY_PORT = "3000" and JAVA_TIMEZONE = "UTC" are injected automatically — do not override them.
• No GCS storage bucket is created by default. Metabase stores everything in PostgreSQL. Add a bucket via storage_buckets only if needed.

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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 Metabase workload

Metabase 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. Because the JVM takes 60–120 seconds to initialise, keep min_instance_count = 1 in production to avoid cold-start delays and probe failures.

• Console: Kubernetes Engine → Workloads → select the Metabase 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 PostgreSQL 15

Metabase stores its entire application state — questions, dashboards, collections, users, permissions, and settings — in a managed Cloud SQL for PostgreSQL 15 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 initialization 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. Secret Manager

The database password is stored as a Secret Manager secret and injected into pods at runtime; plaintext never appears in configuration. Metabase manages its own internal encryption key separately.

• 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. See App_GKE for the Secret Store CSI integration and rotation.

D. Networking & ingress

enable_custom_domain = true by default, so App_GKE provisions a Gateway-based HTTPS ingress out of the box. With no application_domains set, it derives a zero-config <ip>.nip.io hostname from the reserved static IP and a matching Google-managed certificate, so Metabase gets HTTPS immediately. Set application_domains to serve a real custom domain instead; a static IP is reserved by default 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.

E. Cloud Logging & Monitoring

Pod stdout/stderr (including Metabase JVM logs) 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

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3. Metabase Application Behaviour

• First-deploy database setup. An initialization Job runs before the application workload, using postgres:15-alpine to connect to Cloud SQL through the Auth Proxy and idempotently create the application database and user. It is safe to re-run.
• No auto-migration on startup. Unlike some other applications, Metabase does not run schema migrations on every start. Migrations run as part of the Metabase application process on first boot against an already-initialised database — hence the importance of the db-init job completing successfully first.
• Upgrade caution. Metabase migrations are one-way. Downgrading after a migration has run corrupts the schema. Always test upgrades in a staging environment before applying to production.
• Health path. Startup and liveness probes target /api/health, which returns HTTP 200 only when the JVM is fully initialised and connected to PostgreSQL. The startup probe uses a 60-second initial delay with 18 retries (period 10s), giving ~240 seconds total tolerance. Do not reduce these values.
• Admin setup. On first boot Metabase presents a setup wizard in the browser. After setup, the admin credentials are managed inside Metabase itself — no SECRET_KEY or admin password is managed by this module.
• Data sources. Metabase is a BI tool that queries external databases. After deployment, configure data sources in Metabase Admin → Databases. Common GCP-native sources include BigQuery, Cloud SQL PostgreSQL/MySQL, and Google Sheets.
• MB_JETTY_PORT and JAVA_TIMEZONE are fixed. These are injected automatically by Metabase_Common. Overriding them via environment_variables breaks routing or produces incorrect report timestamps.

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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 Metabase are listed; every other input is inherited from App_GKE 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 workload 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	metabase	Base name for resources. Do not change after first deploy.
application_display_name	Metabase Analytics	Friendly name shown in the Console.
application_description	(set)	Workload description annotation.
application_version	v0.51.3	Metabase image version tag; increment to roll out a new version. Never downgrade — migrations are irreversible.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
container_resources	{ cpu_limit = "2000m", memory_limit = "4Gi" }	CPU/memory limits. JVM requires at least 2 GiB; 4 GiB recommended for production.
min_instance_count	1	Minimum replicas. Keep ≥ 1 to avoid 60–120s JVM cold starts.
max_instance_count	5	Maximum replicas (autoscaler ceiling).
container_port	3000	Metabase's Jetty port — must match MB_JETTY_PORT.
enable_cloudsql_volume	true	Cloud SQL Auth Proxy sidecar for Unix socket connections. Required.
enable_vertical_pod_autoscaling	false	Let Autopilot tune resource requests automatically — recommended for JVM right-sizing.

Group 5 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{}	Extra non-secret settings. MB_JETTY_PORT and JAVA_TIMEZONE are injected automatically — do not override.
secret_environment_variables	{}	Map of env var → Secret Manager secret name (e.g., SMTP password).

Group 6 — GKE Backend & Cluster

Variable	Default	Description
service_type	LoadBalancer	How the Service is exposed.
session_affinity	ClientIP	Sticky routing required to keep browser sessions on one pod during HPA scale-out.
workload_type	null	Auto-resolves; Metabase is stateless so use "Deployment".
termination_grace_period_seconds	60	Seconds Kubernetes waits after SIGTERM; allows in-flight queries to complete.

Group 7 — StatefulSet (advanced)

Not recommended for Metabase — it is stateless. See App_GKE for StatefulSet mechanics if needed.

Group 8 — Resource Quota

Variable	Default	Description
enable_resource_quota	false	Cap 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 scheduling.

Group 9 — Reliability Policies

Variable	Default	Description
enable_pod_disruption_budget	true	Protect availability during node upgrades.
pdb_min_available	1	Raise min_instance_count above 1 if you need eviction headroom.
enable_topology_spread	false	Spread pods across zones.

Group 10 — Observability & Health

Variable	Default	Description
startup_probe_config	/api/health, initial delay 60s, failure threshold 18	HTTP probe; total tolerance ~240s for JVM startup. Do not reduce.
health_check_config	/api/health, initial delay 120s, failure threshold 3	Liveness probe.
uptime_check_config	disabled	Optional Cloud Monitoring uptime check.
alert_policies	[]	Optional metric alert policies.

Group 11 — Jobs & Scheduled Tasks

Variable	Default	Description
initialization_jobs	[]	Leave empty to use the built-in db-init job (PostgreSQL database + user creation).
cron_jobs	[]	Scheduled Kubernetes CronJobs for any recurring tasks.

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)

Variable	Default	Description
enable_nfs	false	NFS storage is not required for Metabase — all state is in PostgreSQL.

Group 14 — Cloud Storage & Artifact Registry

Variable	Default	Description
create_cloud_storage	true	Provision GCS buckets when storage_buckets is non-empty.
storage_buckets	[]	Empty by default — Metabase does not require object storage. Add buckets here only if needed (e.g., for Metabase Enterprise S3 storage).
manage_storage_kms_iam / enable_artifact_registry_cmek	false	CMEK options.

Group 16 — Database Backend

Variable	Default	Description
database_type	POSTGRES_15	Fixed — do not change. Metabase requires PostgreSQL.
application_database_name	metabase	Database name. Immutable after first deploy.
application_database_user	metabase	Application user. Immutable after first deploy.
database_password_length	32	Generated password length (16–64).
enable_auto_password_rotation	false	Zero-downtime DB password rotation.

Group 17 — Backup & Maintenance

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 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

Variable	Default	Description
enable_custom_domain	true	Provisions the Gateway HTTPS ingress; derives a zero-config <ip>.nip.io hostname when application_domains is empty.
application_domains	[]	Hostnames to serve.
reserve_static_ip	true	Stable external IP across redeploys.
network_tags	['nfsserver']	Node/pod tags for firewall rules.

Group 20 — Identity-Aware Proxy (IAP)

Variable	Default	Description
enable_iap	false	Require Google sign-in in front of Metabase. Strongly recommended — Metabase's own login is otherwise publicly reachable.
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 & CDN

Variable	Default	Description
enable_cloud_armor	false	Attach a Cloud Armor (WAF) policy to the Ingress backend.
admin_ip_ranges	[]	CIDRs allowed privileged access.
cloud_armor_policy_name	(set)	Policy name.
enable_cdn	false	Enable Cloud CDN on the GKE Ingress backend.

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	Kubernetes Service name.
namespace	Namespace the workload runs in.
service_cluster_ip	In-cluster ClusterIP.
stage_service_cluster_ips	Map of ClusterIPs for stage-specific services.
service_external_ip	External LoadBalancer IP (when a static IP is reserved).
service_url	URL to reach Metabase.
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 endpoint (127.0.0.1 via the Auth Proxy) / port.
storage_buckets	Created Cloud Storage buckets (empty by default).
network_name / network_exists / regions	VPC network, presence, available regions.
container_image / container_registry	Deployed image and Artifact Registry repo.
monitoring_enabled / monitoring_notification_channels	Monitoring status and channels.
initialization_jobs / db_import_job	Names of the setup and (optional) import 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.
kubernetes_ready	Whether the cluster/workload is ready.
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	Metabase requires PostgreSQL; any other engine breaks startup.
enable_cloudsql_volume	true	Critical	Disabling breaks all database connections (Auth Proxy sidecar required).
container_resources.memory_limit	4Gi	Critical	Under 2 GiB the JVM crashes with OutOfMemoryError on startup.
application_database_name / _user	set once	Critical	Immutable after first deploy; renaming recreates the DB/user and destroys all application data.
enable_backup_import	false unless restoring	Critical	Enabling without a valid backup_uri fails the import job.
application_version	increment carefully	Critical	Metabase migrations are one-way; downgrading corrupts the schema. Always test upgrades in staging.
quota_memory_requests / _limits	binary units	Critical	Bare integers are bytes and block all scheduling.
startup_probe_config.failure_threshold	18 (≥ 18)	High	Reducing causes premature pod kills before the JVM completes startup.
min_instance_count	1	High	0 causes 60–120s cold starts; probe failures on first request.
container_resources.cpu_limit	2000m	High	Under 500m JVM JIT compilation stalls startup, triggering probe failures.
session_affinity	ClientIP	High	Without stickiness, multi-pod deployments lose browser session state on scale-out.
enable_iap / enable_cloud_armor	enable for prod	High	Metabase login page is otherwise publicly reachable.
backup_retention_days	7 (raise for prod)	Medium	Too short for compliance retention.
pdb_min_available vs min_instance_count	leave headroom	Medium	1/1 can stall node upgrades (single pod cannot be evicted).
enable_redis	false	Low	Metabase does not use Redis; enabling has no effect.

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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. Metabase-specific application configuration shared with the Cloud Run variant is described in Metabase_Common.