Gatus on Google Cloud Run

Gatus is an open-source, Apache 2.0-licensed developer-oriented status page and health-check monitor written in Go. It polls configured HTTP, TCP, DNS, ICMP, and other endpoints on independent per-endpoint schedules, evaluates simple result conditions (status code, response time, response body content, TLS certificate expiry), and serves a live public status page plus alerting — no external database required. This module deploys Gatus 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 Gatus 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

Gatus runs as a single Go container on Cloud Run v2. The deployment wires together a deliberately small set of Google Cloud services — Gatus has no database, cache, or object-storage dependency of its own:

Capability	Google Cloud service	Notes
Compute	Cloud Run v2	Single Go service, 1 vCPU / 512 MiB by default; CPU always allocated so the watchdog polling loop is never throttled
Database	None	database_type = "NONE"; optional history store is a local SQLite file, no Cloud SQL provisioned
Persistence	Ephemeral disk (default) or NFS (optional, with a caveat)	SQLite history at /data/data.db; see the WAL-journal caveat below before enabling NFS
Object storage	None	Gatus stores nothing in Cloud Storage
Cache / queue	None	No Redis; Gatus has no cache or queue dependency
Secrets	Secret Manager	No auto-generated secrets; only user-supplied secret_environment_variables
Ingress	Cloud Run URL / Cloud Load Balancing	Default run.app URL; optional external HTTPS load balancer + custom domain

Sensible defaults worth knowing up front:

• No database is provisioned. database_type = "NONE" — Gatus's optional history store is a local SQLite file. The database-related variables exist for completeness but are inert unless you deliberately opt in to an external database.
• Configuration is entirely file-based. Every monitored endpoint, alert integration, and storage setting lives in one YAML file baked into the image at build time — there is no per-setting environment variable convention and no runtime config-reload API. Change monitored endpoints by editing modules/Gatus_Common/scripts/config.yaml and redeploying.
• The history store is ephemeral by default, deliberately. Gatus hardcodes SQLite WAL journal mode (confirmed live: no config option or connection-string parameter disables it), and SQLite's own documentation states WAL is unsupported on network filesystems. Cloud Run offers only ephemeral storage or NFS for this — neither is a genuinely safe home for a WAL-mode SQLite file, so the module defaults to ephemeral rather than risking silent corruption. Deploy Gatus_GKE with stateful_pvc_enabled = true (a real block device) if persistent history matters.
• CPU is always allocated (cpu_always_allocated = true). Gatus's watchdog goroutine polls every configured endpoint on its own schedule, independent of inbound HTTP requests. Request-based billing would throttle CPU between page views and silently stall or skip scheduled checks — the monitoring loop is the product, the same rationale used for UptimeKuma.
• Single instance by default (min_instance_count = 1, max_instance_count = 1). Multiple instances would each independently poll every endpoint and duplicate alerts — there is no shared coordination between Gatus instances.
• Public ingress is the default (ingress_settings = "all") so the status page is publicly reachable. Enabling IAP requires Google sign-in and blocks unauthenticated viewing.
• The health endpoint is /health, which returns HTTP 200 as soon as the server binds its port.
• Access control, if any, is configured in config.yaml. Gatus ships with an open status page by default; optional basic-auth or OIDC protection is configured in the security block of config.yaml and requires a rebuild.

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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 Gatus service

Gatus runs as a Cloud Run v2 service. Each deployment creates an immutable revision; traffic can be split across revisions for safe rollouts. Because CPU is always allocated, the watchdog polling loop keeps running between inbound requests.

• 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. Persistence — the SQLite history store

Gatus has no Cloud SQL instance. Its optional history store is a local SQLite file at /data/data.db, baked into the image directory structure at build time. On Cloud Run's default configuration this directory is ephemeral — history does not survive a restart or redeploy.

• Console: Filestore → Instances (when enable_nfs = true).
• CLI:

  # Confirm the injected environment on the running revision:
  gcloud run services describe <service-name> --project "$PROJECT" --region "$REGION" \
    --format='value(spec.template.spec.containers[0].env)'

Before enabling NFS for durable history, read the WAL-journal caveat in §1 Overview and in Gatus_Common — Cloud Run has no block-PVC option, so NFS is the only optional persistence mechanism here and it carries a real corruption risk for a WAL-mode SQLite file. See App_CloudRun for the general NFS (Filestore) mount model.

C. Secret Manager

Gatus generates no secrets at deploy time — there is no database password or encryption key to manage. Secret Manager is used only if you supply your own via secret_environment_variables (for example a ${VAR} referenced inside config.yaml's alerting 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.

D. Networking & ingress

The service is reachable at its run.app URL by default, which allows the public access a status page typically needs. An external HTTPS load balancer with a custom domain, Cloud CDN, and Cloud Armor can be layered on.

• 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.

E. Cloud Logging & Monitoring

Container logs flow to Cloud Logging; Cloud Run metrics flow to Cloud Monitoring, with optional uptime checks and alert policies. Gatus logs each endpoint check's result (success/failure, duration) as it runs.

• 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. Gatus Application Behaviour

• No first-deploy database setup. Gatus has no external database and no migration step. It reads config.yaml, initialises its SQLite history store (if configured), and starts serving immediately. There is no init job by default.
• Ephemeral history store by default. /data/data.db lives on the container's local writable filesystem with nothing mounted unless you opt into NFS. Every restart or redeploy resets check history (the status page itself and all currently-configured checks are unaffected — only the historical results/uptime percentages reset).
• The watchdog polling loop needs allocated CPU. Each configured endpoint is checked on its own independent interval by an in-process goroutine; cpu_always_allocated = true ensures this keeps running between inbound page views.
• Health path. Startup and liveness probes target /health, which returns HTTP 200 as soon as the server binds port 8080. Verify:

  SERVICE_URL=$(gcloud run services describe <service-name> \
    --project "$PROJECT" --region "$REGION" --format='value(status.url)')
  curl -s -o /dev/null -w '%{http_code}\n' "$SERVICE_URL/health"      # -> 200

• View the status page.

  curl -s "$SERVICE_URL/" | head -20     # rendered HTML status page

• Configuration changes require a rebuild. Gatus has no admin UI or API for editing monitored endpoints. Edit modules/Gatus_Common/scripts/config.yaml (add, remove, or modify endpoints entries) and redeploy to apply changes.
• Access is open until you configure it. By default the status page has no authentication. Configure basic-auth or OIDC in config.yaml's security block and redeploy to restrict viewing.

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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 Gatus 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 / 3 — Deployment Environment & Application Identity

Variable	Default	Description
tenant_deployment_id	demo	Short suffix that makes resource names unique per environment.
application_name	gatus	Base name for the service, registry repo, and secrets. Do not change after first deploy.
application_display_name	Gatus	Human-readable name shown in the Console.
application_version	latest	Image version tag; latest maps to a pinned v5.36.0 base. Pin an explicit v5.x.y in production.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision supporting infrastructure only.
container_image_source	custom	custom builds the wrapper image via Cloud Build; prebuilt deploys an image directly.
cpu_limit	1000m	CPU per instance.
memory_limit	512Mi	Memory per instance (gen2 floor is 512Mi).
min_instance_count	1	Minimum instances.
max_instance_count	1	Keep at 1 — replicas would each independently poll every endpoint and duplicate alerts.
container_port	8080	Gatus listens on port 8080.
container_protocol	http1	HTTP/1.1 by default.
cpu_always_allocated	true	Required so the watchdog polling loop is never throttled between requests.
enable_cloudsql_volume	false	Off — Gatus has no database.
enable_image_mirroring	true	Mirror the Gatus image into Artifact Registry.

Group 5 — Access & Networking

Variable	Default	Description
ingress_settings	all	all is required for a public status page.
enable_iap	false	Require Google sign-in. Blocks unauthenticated viewing.

Group 6 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{}	Substitutions for ${VAR}-style references inside config.yaml (e.g. an alerting webhook token), not per-setting overrides.
secret_environment_variables	{}	Map of env var → Secret Manager secret name (optional; none required).

Group 11 — Storage & Filesystem

Variable	Default	Description
enable_nfs	false	Optional durable history mount. Caution: carries a WAL-on-network-filesystem risk — see §1.
nfs_mount_path	/data	NFS mount path; matches the baked-in storage.path in config.yaml.
storage_buckets	[]	Not required — Gatus uses no object storage.

Group 12 — Database Backend

Variable	Default	Description
database_type	NONE	Gatus has no external database; leave NONE.
application_database_name / application_database_user	gatus	Inert unless an external database is deliberately enabled.

Group 13 — Jobs & Scheduled Tasks

Variable	Default	Description
initialization_jobs	[]	Gatus needs no init job; leave empty.
cron_jobs	[]	Optional scheduled Cloud Run jobs.

Group 14 — Observability & Health

Variable	Default	Description
startup_probe	HTTP /health 10s delay	Startup probe. Gatus becomes healthy within seconds.
liveness_probe	HTTP /health 15s delay	Liveness probe.
uptime_check_config	{ enabled=false, path="/health" }	Optional Cloud Monitoring uptime check.

Group 16 — Redis Cache

Variable	Default	Description
enable_redis	false	Not required — Gatus has no Redis dependency.

All other inputs follow standard App_CloudRun behaviour.

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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 / database_name / database_user	Database identifiers — empty for the default NONE engine.
database_password_secret / database_host / database_port	Database endpoint fields — unused for NONE.
storage_buckets	Created Cloud Storage buckets (none by default).
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 any setup jobs (none by default).
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).

Inherited plan-time validation. This module passes its configuration through the App_CloudRun foundation engine, which validates values and combinations at plan time — IAP with no authorized identities, a gen1 runtime with NFS/GCS mounts, an out-of-range container_port/timeout_seconds, a memory value below the gen2 floor. 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.

Setting	Sensible value	Risk	Consequence if wrong
enable_nfs (for durable history)	Leave false; use Gatus_GKE with stateful_pvc_enabled instead	Critical	Gatus hardcodes SQLite WAL journal mode, which SQLite's own documentation states is unsupported on network filesystems — NFS-backed history risks silent corruption over time.
max_instance_count	1	High	Scaling beyond 1 has every replica independently poll every endpoint, duplicating alert notifications with no coordination between instances.
cpu_always_allocated	true	High	Setting false lets Cloud Run throttle CPU between requests, silently stalling or skipping the watchdog's scheduled endpoint checks.
ingress_settings	all	High	internal makes a public status page unreachable from outside the VPC.
enable_iap	only when auth-gated	High	IAP requires Google sign-in for every request, blocking unauthenticated status-page viewing — usually not what a public status page wants.
Gatus security block in config.yaml	Configure if the page has sensitive endpoint names	Medium	Left default, the status page (including all configured endpoint names and their up/down history) is publicly visible to anyone with the URL.
container_port	8080	Medium	Overriding to a value Gatus is not listening on causes every health probe to fail.
memory_limit	512Mi	Low	The gen2 execution environment rejects values below 512Mi at apply time.
application_version	Pin v5.x.y in prod	Low	latest maps to a pinned base (v5.36.0); pin explicitly to control upgrades.

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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. Gatus-specific application configuration shared with the GKE variant is described in Gatus_Common.