Komga on GKE Autopilot

Komga is a free, open-source, self-hosted media server for comics, manga, and digital book collections (Kotlin/Java, Spring Boot). It provides a clean web reading UI, OPDS feeds, collections, read lists, and full-text search over your library. This module deploys Komga 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 Komga 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

Komga runs as a single JVM pod, recommended as a StatefulSet with a block PVC. The deployment wires together a minimal set of Google Cloud services — there is no external database:

Capability	Google Cloud service	Notes
Compute	GKE Autopilot	JVM (Spring Boot) pod, 1 vCPU / 1 GiB by default; single replica
Database	None	Komga uses an embedded SQLite database under /config — no Cloud SQL instance is created
Object storage / block storage	Cloud Storage (GCS FUSE) or PVC	stateful_pvc_enabled = true (default) mounts a real block PVC at /config; disable it to use a GCS-FUSE-backed bucket instead
Secrets	Secret Manager	None generated — Komga has no injectable service secret
Ingress	Cloud Load Balancing	External LoadBalancer, optional custom domain + managed certificate

Sensible defaults worth knowing up front:

• No external database. Komga stores its library index, users, reading progress, and settings in an embedded SQLite database — confirmed via upstream issue #1327 (open, unimplemented feature request for external DB support). database_type = "NONE", enable_redis forced false.
• Official prebuilt image. container_image_source = "prebuilt" deploys gotson/komga directly — no Cloud Build step. enable_image_mirroring = true mirrors it into Artifact Registry (digest-aware copy) to avoid Docker Hub rate limits.
• Block-storage PVC is the recommended layout. stateful_pvc_enabled = true by default runs Komga as a StatefulSet with a per-pod PVC mounted at /config — gcsfuse's lack of real file locking corrupts SQLite WAL files, so a real block volume is preferred over GCS FUSE for production use.
• Single instance only. min_instance_count = 1 and max_instance_count = 1 — Komga serves one shared SQLite library from one volume; do not scale beyond 1.
• Runs as root. Komga's container has no USER directive (confirmed via local container testing), so no gcsfuse/PVC uid/gid mount-option workaround is needed.
• No generated secrets. The admin account is created interactively through Komga's first-run setup wizard at / — there is no master key or JWT secret to seed ahead of time.
• Health endpoint is /actuator/health. Confirmed via local container testing to return 200 {"status":"UP"} unauthenticated. The versioned /api/v1/actuator/health path is auth-gated (401) — do not point probes at it.
• JVM heap sizing is optional. jvm_heap_max (blank by default) sets -Xmx via JAVA_TOOL_OPTIONS.

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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 Komga workload

Komga's pod is scheduled on Autopilot, which bills for the CPU/memory the pod actually requests. With stateful_pvc_enabled = true (default) the workload is a StatefulSet with a stable pod identity and its own PVC.

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

  kubectl get pods,svc,pvc -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. Storage — Komga's persistent state

By default, a real block PersistentVolumeClaim is mounted at /config, holding the embedded SQLite database, Lucene search index, thumbnail cache, and logs. If stateful_pvc_enabled = false, a Cloud Storage bucket is mounted at the same path via the GCS FUSE CSI driver instead (light use only — see the caveats in Komga_Common).

• Console: Kubernetes Engine → Storage (PVCs); Cloud Storage → Buckets (if GCS-FUSE mode).
• CLI:

  kubectl get pvc -n "$NAMESPACE"
  gcloud storage buckets list --project "$PROJECT"     # if using the GCS bucket

See App_GKE for CMEK options and StorageClass details.

C. Secret Manager

Komga has no generated service secret — the admin account is created through the web setup wizard. Secret Manager only holds entries you add yourself via secret_environment_variables.

• Console: Security → Secret Manager.
• CLI:

  gcloud secrets list --project "$PROJECT" --filter="name~komga"

D. 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.

E. Cloud Logging & Monitoring

Pod stdout/stderr flow to Cloud Logging; GKE metrics flow to Cloud Monitoring, with optional uptime checks and alert policies.

• 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. Komga Application Behaviour

• No first-deploy database setup. There is no db-init job — Komga runs its own Flyway schema migrations against the embedded SQLite database on first boot (confirmed via local container logs: org.flywaydb.core.FlywayExecutor, Successfully validated 90 migrations).
• First-run setup wizard. Open the service URL and complete the setup wizard at / to create the initial admin user — there is no seeded credential and no API/CLI path to create one non-interactively.
• Add a library after first login. Once logged in, add a "library" pointing at a mounted media path and trigger a scan. This is a manual operator step; no init job seeds it.
• Health path. Startup and liveness probes target /actuator/health (unauthenticated, 200 {"status":"UP"} once ready). Do not use /api/v1/actuator/health — confirmed via local testing to return 401 Unauthorized even when the app is fully healthy.
• Single shared library, single instance. Komga's SQLite database is a single file on one mounted volume — running more than one replica risks concurrent writers corrupting it. Keep max_instance_count = 1.
• Block PVC over GCS FUSE. When stateful_pvc_enabled = true, enable_gcs_storage_volume is auto-set false inside Komga_Common to avoid a double-mount at /config. If the project's SSD quota is constrained, override stateful_pvc_storage_class = "standard" (HDD) — Komga's SQLite access pattern does not need SSD IOPS.

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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 Komga 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	komga	Base name for resources. Do not change after first deploy.
application_version	latest	Image tag, passed straight through as the gotson/komga tag.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
container_image_source	prebuilt	Deploys the official gotson/komga image directly — no build step.
cpu_limit	1000m	CPU per pod.
memory_limit	1Gi	Memory per pod; raise for very large libraries.
min_instance_count	1	Keep at 1 to avoid cold starts during the Lucene index rebuild on boot.
max_instance_count	1	Do not increase — Komga serves one shared SQLite library.
jvm_heap_max	""	Optional JVM -Xmx via JAVA_TOOL_OPTIONS (e.g. "512m", "1g").
timeout_seconds	300	Maximum request duration (0–3600 seconds).
enable_cloudsql_volume	false	Komga has no Cloud SQL — keep false.
enable_image_mirroring	true	Mirror the Komga image into Artifact Registry before deployment.

Group 5 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{}	Extra non-secret settings.
secret_environment_variables	{}	Map of env var → Secret Manager secret name.
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	ClusterIP	How the Kubernetes Service is exposed — set LoadBalancer for direct external access.
workload_type	null (auto → StatefulSet)	Auto-resolves to StatefulSet when stateful_pvc_enabled = true.
session_affinity	None	No sticky routing required — single replica.
network_tags	["nfsserver"]	Node/pod network tags; nfsserver is required when enable_nfs = true.
termination_grace_period_seconds	60	Seconds to wait after SIGTERM before SIGKILL (lets Komga flush writes).
enable_network_segmentation	false	Create Kubernetes NetworkPolicy resources.

Group 7 — StatefulSet

Variable	Default	Description
stateful_pvc_enabled	true	Enable a per-pod block PVC — recommended for Komga (gcsfuse corrupts its SQLite WAL database). Auto-selects StatefulSet.
stateful_pvc_size	20Gi	Per-pod PVC storage size — size to hold the config, library metadata, and SQLite database.
stateful_pvc_mount_path	/config	Container mount path for the PVC — Komga's KOMGA_CONFIGDIR.
stateful_pvc_storage_class	standard-rwo	StorageClass for PVCs. Override to standard (HDD) if SSD quota is constrained.
stateful_headless_service	null	Create a headless Service for stable pod DNS names.
stateful_pod_management_policy	null	Pod creation order: OrderedReady (safe for Komga) or Parallel.
stateful_update_strategy	null	Update strategy: RollingUpdate or OnDelete.
stateful_fs_group	3000	Pod-level fsGroup. Komga runs as root, so not strictly required, but left set for consistency.

Group 8 — Resource Quota

Variable	Default	Description
enable_resource_quota	false	Create a Kubernetes ResourceQuota in the namespace.
quota_memory_requests / quota_memory_limits	""	Requires a binary suffix (e.g. 4Gi, 8192Mi) when enabled — bare integers are treated as bytes and block pod scheduling.
quota_cpu_requests / quota_cpu_limits / quota_max_pods / quota_max_services / quota_max_pvcs	""	Additional quota dimensions.

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 /actuator/health, 15s delay	Startup probe.
liveness_probe	HTTP /actuator/health, 30s delay	Liveness probe.
startup_probe_config	HTTP /actuator/health	App_GKE-level infrastructure probe.
health_check_config	HTTP /actuator/health	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	[]	Komga needs no default init job.
cron_jobs	[]	Scheduled Kubernetes CronJobs, e.g. for library-maintenance tasks.
additional_services	[]	Sidecar or helper services deployed alongside Komga.

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 is off by default.
nfs_mount_path	/mnt/nfs	Mount path inside the container.

Group 14 — Cloud Storage & Artifact Registry

Variable	Default	Description
create_cloud_storage	true	Create the auto-provisioned storage bucket (used when stateful_pvc_enabled = false).
storage_buckets	[]	Additional buckets to provision.
gcs_volumes	[]	Additional GCS Fuse volume mounts via the CSI driver — e.g. a separate read-mostly comics/books library bucket.
manage_storage_kms_iam / enable_artifact_registry_cmek	false	CMEK options.
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

Not applicable — enable_redis is forced false inside Komga_GKE. All Redis variables are declared for convention parity.

Group 16 — Database Backend

Not applicable — database_type is fixed to NONE. All database-related variables are declared for convention parity and forwarded to the foundation with no effect.

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 / backup_format	restore options	Restore from a backup on deploy.

Group 18 — Custom SQL Scripts

Not applicable — Komga has no SQL database. Declared for convention parity only.

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 20 — Identity-Aware Proxy (IAP)

Variable	Default	Description
enable_iap	false	Require Google sign-in in front of Komga's own auth.
iap_authorized_users / iap_authorized_groups	[]	Who may access.
iap_oauth_client_id / iap_oauth_client_secret	""	Required when IAP is enabled (sensitive).

Group 21 — Cloud Armor

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	default-waf-policy	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 Komga.
storage_buckets	Created Cloud Storage buckets.
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 the setup jobs (empty 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 (repo, trigger, registry).
github_repository_url / github_repository_owner / github_repository_name	CI/CD GitHub 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).

Inherited plan-time validation. This module passes its configuration through the App_GKE foundation engine, which validates values and combinations at plan time. Most mistakes below are caught up front rather than at apply or runtime.

Setting	Sensible value	Risk	Consequence if wrong
max_instance_count	1 (never increase)	Critical	Multiple pods writing the same SQLite file concurrently risks database corruption.
Health probe path	/actuator/health	Critical	/api/v1/actuator/health is auth-gated (401) — using it as the probe path means the pod never becomes Ready even though Komga is fully healthy.
stateful_pvc_enabled vs enable_gcs_storage_volume	Let Komga_Common auto-toggle	Critical	Enabling both mounts two volumes at the same /config path — a double-mount conflict.
stateful_pvc_storage_class	standard-rwo, override to standard under SSD pressure	Medium	SSD-backed PVCs draw the tight SSD_TOTAL_GB quota; a scale-to-zero campaign can exhaust it.
First-run setup wizard	Complete promptly after deploy	High	An unclaimed setup wizard leaves the instance without an admin account; anyone who reaches the URL first can claim it.
min_instance_count	1	Medium	Restarting the single pod triggers cold-start latency including a Lucene index rebuild.
memory_limit	1Gi, raise for large libraries	Medium	Undersized memory can OOM-kill during a large library scan.
container_image_source	prebuilt	Medium	Switching to custom with no Dockerfile fails the build — Komga needs no custom build.
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.

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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. Komga-specific application configuration shared with the Cloud Run variant is described in Komga_Common.