SearXNG on GKE Autopilot

SearXNG is a privacy-respecting, self-hosted metasearch engine that aggregates results from 70+ search services without tracking users or serving ads. This module deploys SearXNG 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 SearXNG uses and how to explore and operate them from the Google Cloud Console and the command line. For the mechanics 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.

---

1. Overview

SearXNG runs as a lightweight Python/Flask web workload. The deployment wires together a minimal set of Google Cloud services:

Capability	Google Cloud service	Notes
Compute	GKE Autopilot	Python/Flask pods, 500m CPU / 512 MiB by default, horizontally autoscaled
Cache / rate limiting	Redis	Optional — disabled by default; enables rate limiting and bot detection
Secrets	Secret Manager	Auto-generated SEARXNG_SECRET (session key) injected via the CSI driver
Ingress	Cloud Load Balancing	External LoadBalancer, optional custom domain + managed certificate

Sensible defaults worth knowing up front:

• No database is provisioned. SearXNG is fully stateless — it aggregates search results at request time and stores nothing.
• No NFS or Cloud Storage is provisioned. SearXNG has no uploads or shared files.
• min_instance_count is fixed at 1. GKE does not support scale-to-zero; the module always keeps at least one pod running.
• Redis is disabled by default. For public-facing deployments, enable Redis to activate rate limiting and bot detection against upstream engine abuse.
• SEARXNG_SECRET is generated automatically and stored in Secret Manager. All pod replicas share the same value via the CSI driver — do not override it with a per-pod random value.
• Health probes target /healthz. SearXNG's built-in health endpoint returns 200 when the application is ready.
• session_affinity = "None". SearXNG is stateless, so requests are distributed evenly across pods.

---

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 SearXNG workload

SearXNG pods are scheduled on Autopilot, which bills for the CPU/memory the pods actually request. Horizontal Pod Autoscaling scales the deployment between the minimum (fixed at 1) and the configured maximum.

• Console: Kubernetes Engine → Workloads → select the SearXNG 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. Redis cache (optional)

When enable_redis = true, SearXNG uses Redis for per-IP rate limiting and bot detection. This is strongly recommended for public-facing deployments to prevent upstream search engine API quota exhaustion. When redis_host is left empty and Redis is enabled, the module defaults to 127.0.0.1 (a sidecar Redis pod).

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

  redis-cli -h <redis-host> ping        # from a host with network access
  redis-cli -h <redis-host> info keyspace

C. Secret Manager — SEARXNG_SECRET

SearXNG_Common auto-generates the SEARXNG_SECRET session key and stores it in Secret Manager. This key signs SearXNG's session cookies and HMAC query parameters; all pod replicas must share the same value. It is injected into pods at runtime via the Kubernetes Secret Store CSI driver.

• Console: Security → Secret Manager.
• CLI:

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

See App_GKE for the Secret Store CSI integration and rotation.

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. 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

---

3. SearXNG Application Behaviour

• Fully stateless. SearXNG fetches results from external search engines at request time and stores nothing locally. No database migrations or initialisation jobs run.
• No first-deploy setup job. Because there is no database, the deployment completes without a db-init step — the pod is ready as soon as the container starts.
• SEARXNG_SECRET is stable. The session key is generated once and persists in Secret Manager across restarts and rolling updates. Rotating it invalidates all active user sessions; avoid rotation in production unless required for security.
• SEARXNG_BIND_ADDRESS is injected automatically as 0.0.0.0:8080 so SearXNG listens on all interfaces at its native port.
• ENABLE_REDIS and REDIS_URL are injected automatically when enable_redis = true. The URL is derived from redis_host and redis_port.
• Health path. Both the startup and liveness probes target /healthz (HTTP GET), which SearXNG answers once the application is fully initialised.
• Fast startups. SearXNG starts in under 5 seconds — no database connections or schema migrations. The startup probe uses a short initial delay of 10 seconds.
• Session affinity is None. Because the session state is stored in the SEARXNG_SECRET-signed cookie (and optionally in Redis), no sticky routing is required.

---

4. Configuration Variables

Variables are grouped exactly as they appear on the deployment platform. Only settings specific to or notable for SearXNG 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	searxng	Base name for resources. Do not change after first deploy.
application_display_name	SearXNG Search	Friendly name shown in the Console.
application_description	(set)	Workload description annotation.
application_version	latest	SearXNG image tag; pin to a specific version for production.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
container_resources	{ cpu_limit="500m", memory_limit="512Mi" }	CPU and memory limits per pod. SearXNG is lightweight; 500m / 512 MiB is sufficient for moderate traffic.
min_instance_count	1 (fixed internally)	Minimum replicas. Fixed at 1 — GKE does not support scale-to-zero.
max_instance_count	3	Maximum replicas (autoscaler ceiling).
container_port	8080	SearXNG's native HTTP port.
container_image_source	prebuilt	Use the official SearXNG image (prebuilt) or build from source (custom).
enable_image_mirroring	true	Mirror the image into Artifact Registry before deployment.
enable_vertical_pod_autoscaling	false	Let Autopilot tune resource requests automatically.
enable_cloudsql_volume	false	Leave false — SearXNG does not use a database.

Group 5 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{ INSTANCE_NAME="SearXNG", AUTOCOMPLETE="" }	Extra settings. SEARXNG_BIND_ADDRESS, ENABLE_REDIS, and REDIS_URL are injected automatically.
secret_environment_variables	{}	Map of env var → Secret Manager secret name for additional secrets (e.g., upstream engine API keys).

Group 6 — GKE Backend & Cluster

Variable	Default	Description
service_type	LoadBalancer	How the Service is exposed.
session_affinity	None	SearXNG is stateless; even distribution is preferred.
workload_type	null	Auto-resolves to Deployment (SearXNG is stateless — leave null).
network_tags	['nfsserver']	Node/pod tags for firewall rules.

Group 7 — StatefulSet

SearXNG is stateless — leave all stateful_pvc_* variables at their defaults (null). See App_GKE for when this group applies.

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 for production deployments.

Group 10 — Observability & Health

Variable	Default	Description
startup_probe / liveness_probe	HTTP /healthz	SearXNG's built-in health endpoint; startup allows 10s initial delay.
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	[]	SearXNG requires no initialisation jobs — leave empty.
cron_jobs	[]	Optional scheduled tasks (e.g., cache warming).

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	SearXNG is stateless — NFS is not required. Leave false.

Group 14 — Cloud Storage & Artifact Registry

Variable	Default	Description
create_cloud_storage	false	SearXNG is stateless — no GCS bucket is required. Leave false.
manage_storage_kms_iam / enable_artifact_registry_cmek	false	CMEK options.

Group 15 — Redis

Variable	Default	Description
enable_redis	false	Enable Redis for rate limiting and bot detection. Recommended for public-facing deployments.
redis_host	""	Redis endpoint. Leave empty to default to 127.0.0.1 when Redis is enabled; set to the Memorystore IP for a managed instance.
redis_port	6379	Redis port.
redis_auth	""	Optional Redis auth password (sensitive).

Group 16 — Database Backend

Variable	Default	Description
database_type	NONE	Fixed — SearXNG does not use a database. Do not change.

Group 17 — Backup & Maintenance

SearXNG is stateless — there is no application data to back up. The backup variables are inherited from the foundation interface but have no practical use. See App_GKE.

Group 18 — Custom SQL Scripts

Not applicable to SearXNG (no database). See App_GKE.

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 SearXNG (internal deployments).
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

Variable	Default	Description
enable_cloud_armor	false	Attach a Cloud Armor (WAF) policy to the Ingress backend. Recommended for public-facing deployments.
admin_ip_ranges	[]	CIDRs allowed privileged access.
cloud_armor_policy_name	default-waf-policy	Policy name.

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.

---

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 SearXNG.
storage_buckets	Created Cloud Storage buckets (empty for SearXNG).
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 any setup jobs (none by default).
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	GitHub connection 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.

---

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
SEARXNG_SECRET (auto-generated)	auto-generated	Critical	If a custom per-pod secret is injected instead, each pod signs cookies with a different key, invalidating sessions across replicas. Always use the auto-generated Secret Manager value.
database_type	NONE	Critical	Changing to a real DB type provisions an unused Cloud SQL instance and breaks startup.
quota_memory_requests / _limits	binary units	Critical	Bare integers are read as bytes by Kubernetes and block all pod scheduling.
enable_redis	true for public deployments	High	Without Redis, SearXNG has no rate limiting; public instances are vulnerable to scraping that exhausts upstream engine quotas.
redis_host	Memorystore IP or explicit value	High	When enable_redis = true and redis_host = "", the module defaults to 127.0.0.1 — there is no sidecar Redis in the default GKE setup, so rate limiting is silently disabled.
vpc_egress_setting (via foundation)	ensure outbound internet access	High	SearXNG fetches results from external engines; outbound internet must not be blocked.
application_version	pinned (not latest)	Medium	Using latest makes deployments non-reproducible; a new SearXNG release may change config schema.
enable_cloud_armor	true for public deployments	Medium	Without Cloud Armor, there is no WAF/DDoS protection on the public endpoint.
enable_iap	true for internal-only	Medium	For internal search deployments, IAP restricts access to authenticated Google accounts.
pdb_min_available vs min_instance_count	leave headroom	Medium	1/1 can stall node upgrades (single pod cannot be evicted).
stateful_pvc_enabled	null	Low	SearXNG is stateless — provisioning a PVC wastes cost and is unused.

---

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. SearXNG-specific application configuration shared with the Cloud Run variant is described in SearXNG_Common.