LubeLogger on GKE Autopilot

LubeLogger is a free, open-source vehicle maintenance and fuel-mileage tracker built on ASP.NET Core (.NET), shipped as a single container image with an embedded LiteDB database. This module deploys LubeLogger 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 LubeLogger 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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What LubeLogger costs on RAD, and how that compares

LubeLogger on RAD's GKE Autopilot module costs about US$42 a month in your own project, with no per-vehicle fee. RAD charges 75 credits once per deployment in your own project (67.5 credits, 10% lower, in a project RAD manages), plus build time. The same app also deploys on Cloud Run for about US$33 a month — see the Cloud Run guide for the lower-cost option. If you only need it occasionally, a RAD-managed project can be deleted and restored within 30 days for a few credits, so that monthly figure becomes a few dollars instead — see Pause it for free, below.

What you pay on RAD

	In a Google Cloud project you own	In a project RAD manages for you
Module fee, once per deployment	75 credits (US$7.50 at the top-up price)	67.5 credits (10% lower)
Build time	A few credits per build	The same
Google Cloud running cost	Billed by Google to your own billing account, about US$42 a month for the default configuration (table below)	Metered hourly in credits; RAD publishes 67 credits a day, about 2,010 a month (about US$201.00 at the top-up price, less on a plan)
Who owns what	You own the project and its billing; RAD deploys and updates it	RAD 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
GKE Autopilot pod, 1x vCPU / 1 GiB	US$36
Cloud NAT and networking	US$5
Cloud Storage (add-ons, backups)	US$1
GKE cluster management fee	shared across every GKE app in the project; US$0 if this is your only cluster, else ~US$73
Total	about US$42

How it compares

• AUTOsist, a commercial fleet-maintenance tracker, charges US$6–7 per vehicle per month, with a US$59-a-month minimum for 5 vehicles on its base Maintenance package.
• RAD's LubeLogger module costs about US$42 a month in your own project — in the same range as AUTOsist's 5-vehicle minimum, but with no per-vehicle fee and no vehicle count ceiling: a household tracking two cars costs exactly the same as a small fleet tracking twenty.
• Self-managed comparison: at 1 vCPU / 1 GiB, a Hetzner CPX22 or DigitalOcean 2 vCPU/4 GB droplet (~US$24/month) would run LubeLogger fine, but you would still run the OS, backups and upgrades yourself.

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

If LubeLogger 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 LubeLogger you only need occasionally — evaluating it, a demo environment, a seasonal or intermittent workload — 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 the database, any VM or the compute resource one by one — the whole project, and everything in it, simply stops.
• Restoring costs a few 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 LubeLogger behind Services_GCP (a GKE cluster) and Project_GCP, that is roughly a handful of credits (under US$1) in total, against the about 80 credits (US$8.00) a full redeploy costs.
• So a month of occasional use can cost a few dollars, not US$42. Deploy LubeLogger, use it for a while, delete the project. Restore it next time you need it, confirm with Update, and delete it again when you're done. You pay only for the module fee once, the builds, and whatever time it was actually live.
• What this needs. You must own the project (not 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 evaluation use fits). Google says most services are fully working again within 36 hours of a restore.
• One real gap: nightly backups do not survive. Backups and other generated files 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 have customised LubeLogger and want to keep that work, copy a backup out (to Google Drive, or a bucket outside the project) before you delete. 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

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 — roughly 80 credits (US$8.00) in total. Deleting saves money only once LubeLogger would otherwise sit unused long enough to clear that redeploy cost against its own running cost — about 6 days or more, both in your own project (about US$1.40 a day) and in a RAD-managed one (67 credits a day).
• Most of the running cost is usually shared. For LubeLogger that is the database. They stop only when nothing else in the project uses them, so deleting this app while something else shares the project saves only this app'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 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 list prices from the Cloud Billing Catalog API; RAD fees and the daily-credit estimate from radmodules.dev/pricing; Delete and restore projects for the pause/restore mechanics and what it says about Cloud Storage objects without soft delete; AUTOsist. Prices change; check each source before relying on a figure.

1. Overview

LubeLogger runs as a single ASP.NET Core pod, recommended as a StatefulSet with a real block-storage PVC. The deployment wires together a minimal set of Google Cloud services — there is no managed database in the default configuration:

Capability	Google Cloud service	Notes
Compute	GKE Autopilot	ASP.NET Core pod, 1 vCPU / 1 GiB by default, fixed at a single replica
Database	None (default)	LubeLogger's default mode uses an internal embedded LiteDB database file — no Cloud SQL instance is created
Object storage / block storage	Cloud Storage + Persistent Disk	A block PVC (recommended, stateful_pvc_enabled = true) at /App/data, plus a small dpkeys GCS bucket for ASP.NET Core Data Protection keys (always GCS-backed)
Cache & queue	None	LubeLogger has no Redis usage and no background worker/queue
Secrets	None	No secrets are generated — the first account is created via self-service registration
Ingress	Cloud Load Balancing	External LoadBalancer by default; optional custom domain + managed certificate

Sensible defaults worth knowing up front:

• No external database by default. database_type = "NONE" — LubeLogger's own embedded LiteDB database file is the source of truth. LubeLogger also supports an optional external Postgres backend via a single POSTGRES_CONNECTION DSN environment variable, but this module does not wire Cloud SQL for it.
• Block-storage PVC is the recommended layout. stateful_pvc_enabled = true (default) runs LubeLogger as a StatefulSet with a per-pod PVC mounted at /App/data — a real block device gives reliable file locking for the embedded LiteDB database, unlike GCS FUSE.
• Single instance only. min_instance_count = 1 and max_instance_count = 1 — LubeLogger's default mode serves one shared database file from one volume; running multiple replicas against the same file corrupts it.
• Runs as root; no fsGroup needed. Confirmed directly against the running image — LubeLogger's official image has no USER directive, so stateful_fs_group defaults to 0 (unset).
• Secure by default. EnableAuth = "true" overrides LubeLogger's own appsettings.json default of fully open access. There is no seeded admin account — the first person to complete the Register form on /Login gains access.
• Prebuilt image, no build step. The module deploys the official ghcr.io/hargata/lubelogger image directly (mirrored into Artifact Registry by default) — there is no Dockerfile or Cloud Build involved.
• Externally reachable by default. service_type = "LoadBalancer" — LubeLogger is a public-facing web application, not an internal-only workload.

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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 LubeLogger workload

LubeLogger runs as a single pod (StatefulSet by default), which Autopilot bills for based on requested CPU/memory.

• Console: Kubernetes Engine → Workloads → select the LubeLogger workload to see the pod, revisions, and events. Kubernetes Engine → Services & Ingress shows the external IP.
• CLI:

  kubectl get pods,svc -n "$NAMESPACE"
  kubectl logs -n "$NAMESPACE" statefulset/<service-name> --tail=100

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

B. Persistent storage — block PVC and Cloud Storage

The default layout (stateful_pvc_enabled = true) provisions a per-pod Persistent Disk-backed PVC mounted at /App/data — this holds the embedded LiteDB database file and uploaded photos/receipts/documents. A separate, small Cloud Storage bucket (dpkeys) is always mounted via GCS FUSE at the fixed path /root/.aspnet/DataProtection-Keys, independent of the PVC.

• Console: Kubernetes Engine → Storage (PVCs); Cloud Storage → Buckets.
• CLI:

  kubectl get pvc -n "$NAMESPACE"
  gcloud storage buckets list --project "$PROJECT" --filter="name~lubelogger"

See App_GKE for StorageClass, CMEK, and GCS Fuse mount options.

C. 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.

D. Cloud Logging & Monitoring

Pod stdout/stderr flow to Cloud Logging; GKE 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. LubeLogger Application Behaviour

• No first-deploy database setup. There is no db-init job — LubeLogger initialises its own LiteDB database file and directory structure (config/, documents/, images/, temp/, themes/, translations/ under /App/data) on first boot.
• No fixed admin credential. Open the service, go to /Login, and submit the Register form — that becomes the usable account. Complete this immediately after first deploy: EnableAuth = "true" restricts the rest of the app, but registration itself is open to anyone who can reach the URL until a first account exists.
• Health path. Startup and liveness probes target /Login — LubeLogger's public, unauthenticated page. The app root / is [Authorize]-gated and would fail an unauthenticated probe even on a healthy container.
• Optional external Postgres. LubeLogger supports a single POSTGRES_CONNECTION DSN environment variable (Host=<host>;Port=5432;Username=<user>;Password=<pass>;Database=<db>;) to use an external Postgres database instead of the embedded LiteDB file. This module does not provision Cloud SQL for this path.
• Single instance, always. max_instance_count is fixed at 1 — LubeLogger's default mode has no distributed-locking or multi-writer support for its embedded database.
• Runs as root. Confirmed via docker inspect/docker exec against the actual image — no USER directive, process runs as uid 0. Relevant if you ever add a restricted securityContext — the default configuration needs none.

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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 LubeLogger 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_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	lubelogger	Base name for resources. Do not change after first deploy.
application_version	latest	Image tag on ghcr.io/hargata/lubelogger. Since the image is prebuilt (not custom-built), this directly selects the released version.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
min_instance_count	1	Kept at 1 to avoid cold starts.
max_instance_count	1	Must stay at 1 — LubeLogger's default mode serves one shared database file.
cpu_limit	1000m	CPU per pod.
memory_limit	1Gi	Memory per pod.
timeout_seconds	300	Maximum request duration (0–3600 seconds).
enable_cloudsql_volume	false	LubeLogger's default mode has no Cloud SQL.
enable_image_mirroring	true	Mirror the LubeLogger image into Artifact Registry before deployment.

Group 5 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{}	Extra non-secret settings, merged with the module's default EnableAuth = "true".
secret_environment_variables	{}	Map of env var → Secret Manager secret name. Use this for POSTGRES_CONNECTION if wiring the optional external Postgres backend.
secret_propagation_delay	30	Seconds to wait after secret creation before proceeding.
secret_rotation_period	2592000s	Secret Manager rotation notification frequency.

Group 6 — GKE Backend & Cluster

Variable	Default	Description
service_type	LoadBalancer	LubeLogger is a public-facing web application, so it defaults to external access.
workload_type	null (auto → StatefulSet)	Auto-resolves to StatefulSet when stateful_pvc_enabled = true.
session_affinity	None	No sticky routing needed — single replica.
network_tags	["nfsserver"]	Node/pod network tags; only relevant if enable_nfs = true.
termination_grace_period_seconds	60	Seconds to wait after SIGTERM before SIGKILL (lets LubeLogger flush writes).
enable_network_segmentation	false	Create Kubernetes NetworkPolicy resources.

Group 7 — StatefulSet

Variable	Default	Description
stateful_pvc_enabled	true	Recommended for LubeLogger — a real block PVC gives reliable file locking for the embedded LiteDB database.
stateful_pvc_size	20Gi	Per-pod PVC storage size — sized for the LiteDB database, uploaded documents/receipts, and overhead.
stateful_pvc_mount_path	/App/data	Container mount path for the PVC — must match LubeLogger's data directory.
stateful_pvc_storage_class	standard-rwo	Kubernetes StorageClass for PVCs; use premium-rwo for higher IOPS.
stateful_headless_service	null	Create a headless Service for stable pod DNS names.
stateful_pod_management_policy	null	Pod creation order: OrderedReady or Parallel.
stateful_update_strategy	null	Update strategy: RollingUpdate or OnDelete.
stateful_fs_group	0	Left unset — LubeLogger's official image runs as root and needs no fsGroup to write to the PVC.

Group 8 — Resource Quota

Variable	Default	Description
enable_resource_quota	false	Create a Kubernetes ResourceQuota in the application namespace.
quota_memory_requests / quota_memory_limits	""	Requires a binary suffix (e.g. 4Gi, 8192Mi) per convention when set.

Group 9 — Reliability Policies

Variable	Default	Description
enable_pod_disruption_budget	true	Protect availability during node upgrades.
pdb_min_available	1	Minimum pods available during voluntary disruptions.

Group 10 — Observability & Health

Variable	Default	Description
startup_probe	HTTP /Login 15s delay	Startup probe.
liveness_probe	HTTP /Login 30s delay	Liveness probe.
startup_probe_config	HTTP /Login	App_GKE-level infrastructure probe.
health_check_config	HTTP /Login	App_GKE-level 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	[]	LubeLogger's default mode needs no init job.
cron_jobs	[]	No platform-scheduled recurring tasks by default.
additional_services	[]	Sidecar or helper services deployed alongside LubeLogger.

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 14 — Cloud Storage & Artifact Registry

Variable	Default	Description
create_cloud_storage	true	Create the storage and dpkeys GCS buckets.
storage_buckets	[]	Additional buckets to provision.
gcs_volumes	[]	Additional GCS Fuse volume mounts via the CSI driver.
max_images_to_retain	7	Maximum recent Artifact Registry images to keep.
delete_untagged_images	true	Automatically delete untagged images.
image_retention_days	30	Days after which images are eligible for deletion.

Group 15 — Redis

Variable	Default	Description
enable_redis	true (foundation default)	Forwarded for compatibility; LubeLogger_GKE forces it false — LubeLogger needs no Redis.

Group 16 — Database Backend

Variable	Default	Description
database_type	NONE	Fixed — LubeLogger's default mode has no Cloud SQL database.

Group 19 — Custom Domain, Static IP & Networking

Variable	Default	Description
enable_custom_domain	true	Provision Ingress for custom hostnames + managed certificate.
application_domains	[]	Hostnames to serve.
reserve_static_ip	true	Stable external IP across redeploys.

Group 22 — VPC Service Controls & Audit Logging

Variable	Default	Description
enable_vpc_sc	false	Enforce a VPC-SC perimeter (requires organization_id).
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.
service_external_ip	External LoadBalancer IP (when a static IP is reserved).
service_url	URL to reach LubeLogger.
storage_buckets	Created Cloud Storage buckets (storage, dpkeys).
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	Names of setup jobs (none by default).
statefulset_name	Name of the StatefulSet.
deployment_id / tenant_id / resource_prefix	Naming identifiers.
project_id / project_number	Project identifiers.
cicd_enabled / cicd_configuration	CI/CD status and details.
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).

Inherited plan-time validation. This module passes its configuration through the App_GKE foundation engine, which validates values and combinations at plan time. 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
max_instance_count	1	Critical	LubeLogger's default mode serves one shared embedded database file from one volume; more than one replica risks database corruption from concurrent writers. Enforced by a plan-time validation guard.
stateful_pvc_enabled	true	High	A real block PVC gives reliable file locking; falling back to GCS FUSE for /App/data (by setting this false) risks lock contention under concurrent writes.
stateful_pvc_mount_path	/App/data	Critical	Must match LubeLogger's actual data directory — a wrong path means the database and uploads are written to ephemeral pod storage and lost on every restart.
storage/dpkeys buckets, or the PVC	Never delete	Critical	Losing /App/data (PVC or storage bucket) loses every vehicle record; losing dpkeys invalidates all existing login sessions (recoverable — forces re-login only).
EnableAuth	true (default)	Critical	Setting it to false reverts to LubeLogger's fully open-access mode — anyone with the URL can view/edit all data with no login at all.
First-run registration	Complete immediately after deploy	High	Until a first account is registered, the Register form is reachable by anyone who can reach the URL.
startup_probe/liveness_probe path	/Login	Critical	Pointing probes at / (or any [Authorize]-gated path) fails the probe on an otherwise-healthy pod — it never becomes Ready.
workload_type	leave null (auto)	High	Setting workload_type = "Deployment" alongside stateful_pvc_enabled = true fails at plan time — a PVC template requires a StatefulSet.
database_type	NONE (default)	High	LubeLogger's default mode ignores this setting entirely; changing it does not connect LubeLogger to a Cloud SQL instance — use POSTGRES_CONNECTION instead for the optional external Postgres path.
quota_memory_requests / _limits	binary units (4Gi, 8192Mi)	Critical	Bare integers are bytes and block all pod scheduling in the namespace.
enable_pod_disruption_budget	true	Medium	Disabling allows GKE to evict the pod during maintenance with no protection.
service_type	LoadBalancer (default)	Medium	Setting to ClusterIP makes the public web UI unreachable from outside the cluster.

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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. LubeLogger-specific application configuration shared with the Cloud Run variant is described in LubeLogger_Common.

Related guides

• Hands-on lab: LubeLogger on GKE Autopilot — deploy it step by step, with the console screens and commands at each stage.
• LubeLogger on Google Cloud Run — the same application on Cloud Run, for when you need the other deployment target.
• LubeLogger Common — Shared Application Configuration — the configuration shared by both deployment targets.
• Deployed alongside Grocy on GKE Autopilot, Mealie on GKE Autopilot, Homebox on GKE Autopilot, Wallos on GKE Autopilot in the Home & Life Management solution.