Nextcloud on GKE Autopilot

Nextcloud is the leading self-hosted file sync and collaboration platform, trusted by 400 million users across 100,000+ organisations — including governments and healthcare providers seeking a GDPR-compliant alternative to Google Drive and OneDrive. This module deploys Nextcloud 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 Nextcloud 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.

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1. Overview

Nextcloud runs as a PHP/Apache workload. The deployment wires together a focused set of Google Cloud services:

Capability	Google Cloud service	Notes
Compute	GKE Autopilot	PHP/Apache pods, 2 vCPU / 4 GiB by default, horizontally autoscaled
Database	Cloud SQL for MySQL 8.0	Required — Nextcloud does not support PostgreSQL in this deployment
Shared files	Filestore (NFS)	config/ and data/ directories shared across all replicas
Object storage	Cloud Storage	A nc-data bucket provisioned per deployment
Cache & locking	Redis	Enabled by default; prevents file-locking conflicts across replicas
Secrets	Secret Manager	Auto-generated admin password; post-install config secrets
Ingress	Cloud Load Balancing	External LoadBalancer, optional custom domain + managed certificate

Sensible defaults worth knowing up front:

• MySQL 8.0 is mandatory. The database engine is fixed; selecting PostgreSQL or NONE breaks startup.
• NFS is enabled by default. All replicas must share config.php and the user data directory. Without NFS every pod restart discards files.
• Redis is enabled by default. Without a shared cache and lock backend, concurrent writes across replicas cause "File is locked" errors.
• PHP limits are baked into the container image at build time. Changing php_memory_limit, upload_max_filesize, or post_max_size requires a new Cloud Build run.
• The admin password is generated automatically and stored in Secret Manager; you never set it in plain text.
• First-boot is intentionally slow. Nextcloud runs occ maintenance:install synchronously before Apache starts. The startup probe allows up to 10 minutes for the first installation to complete.

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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 Nextcloud workload

Nextcloud 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.

• Console: Kubernetes Engine → Workloads → select the Nextcloud 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 "$NAMESPACE"          # current vs target utilisation
  # Run an occ command inside a running pod:
  POD=$(kubectl get pods -n "$NAMESPACE" -o name | grep nextcloud | head -1)
  kubectl exec -n "$NAMESPACE" -it "$POD" -- php occ status
  kubectl exec -n "$NAMESPACE" -it "$POD" -- php occ db:add-missing-indices

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

B. Cloud SQL for MySQL 8.0

Nextcloud stores all application data (files metadata, users, shares, calendar, and contacts) in a managed Cloud SQL for MySQL 8.0 instance. Pods reach it privately through the Cloud SQL Auth Proxy sidecar over a Unix socket at 127.0.0.1:3306 so no public IP is exposed. On first deploy an initialization Job creates the application database and user with utf8mb4 collation.

• 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"
  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. Filestore (NFS) and Cloud Storage

Nextcloud data is written to a Filestore (NFS) share mounted into every pod. entrypoint.sh symlinks /var/www/html/config → /mnt/nfs/nextcloud-config and sets NEXTCLOUD_DATA_DIR=/mnt/nfs/nextcloud-data so all replicas share the same config.php and user files. A Cloud Storage nc-data bucket is also provisioned per deployment and the workload service account is granted access automatically.

• Console: Filestore → Instances for the NFS share; Cloud Storage → Buckets for the data bucket.
• CLI:

  gcloud filestore instances list --project "$PROJECT"
  gcloud storage buckets list --project "$PROJECT"
  gcloud storage ls gs://<nc-data-bucket>/
  # Confirm the NFS share is mounted inside a pod:
  kubectl exec -n "$NAMESPACE" deploy/<service-name> -- df -h | grep -i nfs

See App_GKE for NFS provisioning, GCS Fuse, and CMEK options.

D. Redis cache and file locking

Redis backs Nextcloud's distributed cache (memcache.distributed) and file locking (filelocking.enabled). With more than one replica this is mandatory — without it concurrent writes produce "File is locked" HTTP 503 errors. When no external Redis host is configured and NFS is enabled, the NFS server IP is used as the Redis endpoint.

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

  redis-cli -h <redis-host> ping
  redis-cli -h <redis-host> info keyspace

E. Secret Manager

The Nextcloud admin password and four post-installation config secrets (instance ID, password salt, app secret, and optionally the Redis auth password) are stored in Secret Manager and injected into pods at runtime. The three config secrets start as "UNSET" placeholder values; the container's post-install hook writes the real values after occ maintenance:install completes.

• Console: Security → Secret Manager.
• CLI:

  gcloud secrets list --project "$PROJECT" --filter="name~nextcloud"
  gcloud secrets versions access latest --secret=<admin-password-secret> --project "$PROJECT"

The database password secret name is in the Outputs. See App_GKE for the Secret Store CSI integration and rotation.

F. 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. Custom domains are also added to Nextcloud's NEXTCLOUD_TRUSTED_DOMAINS list automatically.

• 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.

G. Cloud Logging & Monitoring

Pod stdout/stderr 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. Nextcloud Application Behaviour

• First-deploy database setup. An initialization Job creates the Nextcloud database and user with utf8mb4 character set and grants privileges before the application starts. It is idempotent and safe to re-run.
• occ maintenance:install on first boot. On the very first start Nextcloud runs its installation routine synchronously before Apache begins serving. This can take several minutes on a cold Cloud SQL instance. The startup probe allows up to 10 minutes (60 s initial delay + 20 failures × 15 s period) for this to complete.
• Post-install config secrets. After occ maintenance:install completes, a hook in the container writes the real instanceid, passwordsalt, and secret values to Secret Manager. Subsequent pod starts read these back to reconstruct config.php without requiring NFS.
• PHP upgrade on start. NEXTCLOUD_UPDATE=1 is set by default, so Nextcloud runs occ upgrade automatically on every container start. This is intentional for minor version bumps. Set NEXTCLOUD_UPDATE=0 in environment_variables and manage upgrades manually when crossing major versions.
• Trusted domains. Nextcloud enforces a trusted-domain whitelist. The module seeds NEXTCLOUD_TRUSTED_DOMAINS with the cluster-internal DNS name and any application_domains. Requests from unlisted hostnames receive an "Access through untrusted domain" error.
• NFS config symlink. When NFS is mounted, entrypoint.sh symlinks /var/www/html/config → /mnt/nfs/nextcloud-config. This is what allows all replicas to share the same config.php.
• Health path. Startup and liveness probes target /status.php, which returns an HTTP 200 with a JSON status object regardless of Nextcloud's setup state — making it the canonical health endpoint.
• Admin login. The initial admin username is configurable; the password is retrieved from Secret Manager (see §2.E).

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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 Nextcloud 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	nextcloud	Base name for resources. Do not change after first deploy.
application_display_name	Nextcloud	Friendly name shown in the Console.
application_description	Nextcloud self-hosted collaboration and file sharing platform on GKE Autopilot	Workload description annotation.
application_version	30	Nextcloud image version tag; increment to roll out a new version.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
cpu_limit	2000m	CPU per pod; 2 vCPU recommended.
memory_limit	4Gi	Memory per pod; 4 GiB recommended.
container_resources	{ cpu_limit="1000m", memory_limit="512Mi" }	Structured resource object; overrides cpu_limit/memory_limit when set.
min_instance_count	1	Minimum replicas. Keep ≥ 1 for WebDAV clients that maintain persistent connections.
max_instance_count	5	Maximum replicas. Requires Redis + NFS when > 1.
container_port	80	Nextcloud/Apache listens on port 80.
enable_cloudsql_volume	true	Cloud SQL Auth Proxy sidecar for socket connections.
enable_vertical_pod_autoscaling	false	Let Autopilot tune resource requests automatically.

Group 5 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{ SMTP_HOST = "", SMTP_PORT = "25", SMTP_USER = "", SMTP_PASSWORD = "", SMTP_SSL = "false", EMAIL_FROM = "ghost@example.com" }	Extra non-secret settings injected into the pod (the default seeds empty SMTP placeholders). Core Nextcloud vars are set automatically.
secret_environment_variables	{}	Map of env var → Secret Manager secret name.
secret_rotation_period	2592000s	Secret Manager rotation notification frequency.
secret_propagation_delay	30	Seconds to wait after secret creation before proceeding.

Group 6 — GKE Backend & Cluster

Variable	Default	Description
gke_cluster_name	""	Target GKE cluster. Auto-discovered when empty.
namespace_name	""	Kubernetes namespace. Auto-generated when empty.
workload_type	null	Auto-resolves to StatefulSet when stateful_pvc_enabled = true.
service_type	LoadBalancer	How the Service is exposed.
session_affinity	ClientIP	Sticky routing; recommended for stateful file operations.
network_tags	['nfsserver']	nfsserver tag is required for NFS connectivity.
termination_grace_period_seconds	30	Grace period before SIGKILL.

Group 7 — StatefulSet

Variable	Default	Description
stateful_pvc_enabled	null	Enables per-pod PVC templates; auto-selects StatefulSet when true.
stateful_pvc_size	10Gi	Storage size for each per-pod PVC.
stateful_pvc_mount_path	/data	Container path for the per-pod PVC.
stateful_pvc_storage_class	standard-rwo	Kubernetes StorageClass for PVC provisioning.
stateful_headless_service	null	Creates a headless Service for stable pod DNS entries.
stateful_pod_management_policy	null	OrderedReady or Parallel.
stateful_update_strategy	null	RollingUpdate or OnDelete.
stateful_fs_group	0	GID set as pod-level fsGroup for PVC ownership.

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; recommended for min_instance_count > 1.

Group 10 — Observability & Health

Variable	Default	Description
startup_probe	{ path="/status.php", initial_delay_seconds=60, failure_threshold=20 }	Allows up to ~5 minutes for first-boot occ maintenance:install.
liveness_probe	{ path="/status.php", initial_delay_seconds=120, failure_threshold=3 }	Restarts the container after 3 consecutive failures.
uptime_check_config	{ enabled=false }	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.
cron_jobs	[]	Kubernetes CronJobs for recurring scheduled tasks.
additional_services	[]	Additional sidecar or companion GKE services.

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	true	Shared Filestore volume for Nextcloud config and data. Required for multi-replica.
nfs_mount_path	/mnt/nfs	Mount path inside the container.
nfs_volume_name	nfs-data-volume	Kubernetes volume name for the NFS mount.
nfs_instance_name	""	Existing NFS GCE VM name. Auto-discovered when empty.
nfs_instance_base_name	app-nfs	Base name for inline NFS VM when none exists.

Group 14 — Cloud Storage & Artifact Registry

Variable	Default	Description
create_cloud_storage	true	Provision the configured buckets (the nc-data bucket comes from Nextcloud_Common).
storage_buckets	[]	Additional GCS buckets beyond the auto-provisioned nc-data bucket.
gcs_volumes	[]	GCS buckets to mount via GCS Fuse CSI driver.
manage_storage_kms_iam / enable_artifact_registry_cmek	false	CMEK options.
max_images_to_retain	7	Maximum recent Artifact Registry images to keep.

Group 15 — Redis Cache

Variable	Default	Description
enable_redis	true	Use Redis for distributed caching and file locking.
redis_host	""	Leave empty to use the NFS server IP; set explicitly when NFS is disabled.
redis_port	6379	Redis port.
redis_auth	""	Optional Redis auth password (sensitive).

Group 16 — Database Backend

Variable	Default	Description
database_type	MYSQL_8_0	Fixed — do not change.
application_database_name	gkeappdb	Database name. Immutable after first deploy.
application_database_user	gkeappuser	Application user. Immutable after first deploy.
db_name	nextcloud	Convenience alias forwarded to Nextcloud_Common as db_name.
db_user	nextcloud	Convenience alias forwarded to Nextcloud_Common as db_user.
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 / backup_format	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	Provision Ingress for custom hostnames + managed certificate.
application_domains	[]	Custom hostnames; also added to NEXTCLOUD_TRUSTED_DOMAINS.
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 Nextcloud.
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	default-waf-policy	Policy name.
enable_cdn	false	Enable Cloud CDN on the 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.

Group 23 — Nextcloud Application Settings

Variable	Default	Description
nextcloud_admin_user	admin	Initial administrator username. Change from the default for public-facing deployments.
php_memory_limit	512M	PHP memory limit — baked into the container image at build time. Increase for large file operations.
upload_max_filesize	512M	Maximum upload file size — baked into the image. Increase for video or archive uploads.
post_max_size	512M	PHP POST body limit — must be ≥ upload_max_filesize.

Email / SMTP

There are no dedicated SMTP variables — outbound email is configured through the environment_variables map (Group 5), whose default seeds the placeholders SMTP_HOST (empty = email disabled; password resets and share notifications will not work), SMTP_PORT (25), SMTP_USER, SMTP_PASSWORD, SMTP_SSL (false), and EMAIL_FROM. Set them to your mail relay's values to enable email.

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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 Nextcloud (appends /login to the base URL).
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 Auth Proxy) / port.
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 / 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 / cicd_configuration	CI/CD status and details.
github_repository_url / github_repository_owner / github_repository_name	CI/CD repo 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	MYSQL_8_0	Critical	Nextcloud requires MySQL; other engines break the init job and startup.
enable_nfs	true	Critical	Without shared storage all user files and config.php are lost on pod restart.
enable_cloudsql_volume	true	Critical	Nextcloud connects via Unix socket; removing the sidecar breaks all DB connections on startup.
application_database_name / _user	set once	Critical	Immutable after first deploy; renaming recreates the DB/user and destroys data.
application_domains	include all access hostnames	Critical	Nextcloud blocks requests from unlisted domains with "Access through untrusted domain".
enable_backup_import	false unless restoring	Critical	Enabling without a valid backup_uri fails the import job.
quota_memory_requests / _limits	binary units	Critical	Bare integers are bytes and block all scheduling.
enable_redis	true	High	With > 1 replica, file locks become stale and concurrent writes return HTTP 503.
redis_host	"" or explicit IP	High	No valid Redis endpoint when NFS is off and no host is set.
upload_max_filesize / post_max_size	increase for large files	High	Baked into image; files above the limit silently fail. post_max_size must be ≥ upload_max_filesize.
memory_limit	4Gi	High	Too little memory causes PHP OOM during large uploads or thumbnail generation.
NEXTCLOUD_UPDATE	1 (default) or 0	High	Leaving 1 on a major-version upgrade can corrupt the database. Set to 0 and run occ upgrade manually across major versions.
min_instance_count	1	High	0 causes cold-start disconnections for WebDAV sync clients.
max_instance_count > 1	requires Redis + NFS	High	Multiple replicas without Redis cause file-locking errors and possible data corruption.
pdb_min_available vs min_instance_count	leave headroom	Medium	1/1 can stall node upgrades (single pod cannot be evicted).
nextcloud_admin_user	change from admin	Medium	Default admin is a common brute-force target on public deployments.
enable_iap / enable_cloud_armor	enable for admin-facing	Medium	Without these the Nextcloud admin panel is publicly reachable.
backup_retention_days	7 (raise for prod)	Medium	Too short for compliance retention.
php_memory_limit	512M (raise for heavy use)	Medium	Baked into image; requires rebuild to change.

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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. Nextcloud-specific application configuration shared with the Cloud Run variant is described in Nextcloud_Common.