Reference

Crossplane S3 ProviderConfig¶

Type: Reference (Information-oriented)

Complete reference documentation for the Crossplane AWS S3 ProviderConfig configured for Hetzner Object Storage.

Overview¶

The hetzner-s3 ProviderConfig enables Crossplane’s Upbound AWS S3 provider to work with Hetzner Object Storage (S3-compatible storage). This configuration is infrastructure-managed via OpenTofu and deployed through the kube-hetzner module.

Infrastructure Location:

Template: kube-hetzner/extra-manifests/50-B-crossplane-provider-s3.yaml.tpl
Applied by: OpenTofu during tofu apply
Namespace: crossplane-system

Complete Configuration¶

apiVersion: aws.upbound.io/v1beta1
kind: ProviderConfig
metadata:
  name: hetzner-s3
  namespace: crossplane-system
spec:
  credentials:
    source: Secret
    secretRef:
      name: hetzner-s3-creds
      namespace: crossplane-system
      key: credentials

  # AWS-specific validations that won't work with Hetzner
  skip_credentials_validation: true
  skip_metadata_api_check: true
  skip_requesting_account_id: true
  skip_region_validation: true  # Allow Hetzner regions (fsn1, nbg1, hel1)

  # Enable path-style S3 access (required for S3-compatible storage)
  s3_use_path_style: true

  # Custom endpoint for Hetzner Object Storage (production region)
  endpoint:
    hostnameImmutable: true  # Required for S3-compatible storage
    partitionId: aws  # Force AWS partition to bypass validation
    services:
      - s3  # CRITICAL: Apply custom endpoint to S3 service
    url:
      type: Static
      static: https://fsn1.your-objectstorage.com

Configuration Fields¶

Credentials¶

credentials:
  source: Secret
  secretRef:
    name: hetzner-s3-creds
    namespace: crossplane-system
    key: credentials

Description: References Kubernetes Secret containing S3 access credentials.

Secret Format (INI):

[default]
aws_access_key_id = <HETZNER_S3_ACCESS_KEY>
aws_secret_access_key = <HETZNER_S3_SECRET_KEY>

Managed By: OpenTofu (created from .env variables)

TF_VAR_hetzner_s3_access_key
TF_VAR_hetzner_s3_secret_key

Important:

Must use INI format (not JSON)
Same credentials used for etcd backups and Loki

Skip Flags¶

skip_credentials_validation¶

skip_credentials_validation: true

Required: Yes Default: false Purpose: Bypasses AWS STS API validation that won’t work with Hetzner S3 Why Needed: Hetzner doesn’t implement AWS STS GetCallerIdentity API

skip_metadata_api_check¶

skip_metadata_api_check: true

Required: Yes Default: false Purpose: Skips AWS EC2 Metadata API verification Why Needed: Kubernetes pods don’t have access to AWS metadata service

skip_requesting_account_id¶

skip_requesting_account_id: true

Required: Yes Default: false Purpose: Prevents provider from requesting AWS account ID Why Needed: Account ID concept doesn’t exist in Hetzner S3

skip_region_validation¶

skip_region_validation: true

Required: Yes Default: false Purpose: Allows Hetzner region codes (fsn1, nbg1, hel1) instead of AWS regions Why Needed: Hetzner uses custom region codes, not AWS region naming

S3 Configuration¶

s3_use_path_style¶

s3_use_path_style: true

Required: Yes Default: false Purpose: Enables path-style S3 access (https://endpoint/bucket/key instead of https://bucket.endpoint/key) Why Needed: Required for S3-compatible storage services

Endpoint Configuration¶

hostnameImmutable¶

endpoint:
  hostnameImmutable: true

Required: Yes Default: false Purpose: Prevents AWS SDK from modifying endpoint hostname based on bucket name Why Needed: S3-compatible storage doesn’t support virtual-hosted-style auto-hostname modification Effect: Endpoint stays exactly as specified

partitionId¶

endpoint:
  partitionId: aws

Required: Yes Default: Auto-detected Purpose: Forces AWS partition to bypass validation Why Needed: Provider validates partition based on region; custom regions would fail without this Valid Values: aws, aws-cn, aws-us-gov

services¶

endpoint:
  services:
    - s3

Required: CRITICAL - Yes Default: Empty (all services) Purpose: Specifies which AWS services should use the custom endpoint Why Needed: Without this, provider ignores custom endpoint for S3 and tries to connect to s3.{region}.amazonaws.com Critical: This is the most important field - without it, Crossplane will fail to connect

url¶

endpoint:
  url:
    type: Static
    static: https://fsn1.your-objectstorage.com

Required: Yes Type: Static (fixed URL) or Dynamic (constructed from variables) Format: Must include https:// protocol prefix Regional Endpoints:

https://fsn1.your-objectstorage.com - Falkenstein (production)
https://nbg1.your-objectstorage.com - Nürnberg
https://hel1.your-objectstorage.com - Helsinki (DR)

Important:

Endpoint URL is stored in .env file variable TF_VAR_production_s3_endpoint
Already includes https:// prefix - don’t add it again in template

Supported Regions¶

Hetzner Object Storage regions that can be used in Bucket resources:

Region Code	Location	Purpose	Endpoint
`fsn1`	Falkenstein, Germany	Production (default)	`https://fsn1.your-objectstorage.com`
`nbg1`	Nürnberg, Germany	Production alternative	`https://nbg1.your-objectstorage.com`
`hel1`	Helsinki, Finland	Disaster Recovery	`https://hel1.your-objectstorage.com`

Recommendation: Use fsn1 for production workloads (same region as cluster for lowest latency).

Bucket Naming Convention¶

CRITICAL: Hetzner S3 bucket names are globally unique across all Hetzner customers (like AWS S3). You cannot use generic names like “backup”, “logs”, or “artifacts” - they will fail with “BucketAlreadyExists” error because other customers have already claimed them.

Naming Schema: LOCALPART-NAMESPACE-kup6s

Components:

LOCALPART: Descriptive purpose (e.g., “gitlab-artifacts”, “uploads”, “backups”, “logs-loki”)
NAMESPACE: Kubernetes namespace (optional for infrastructure buckets)
kup6s: Project identifier suffix (mandatory)

Examples:

# Application bucket
metadata:
  name: gitlab-artifacts-gitlabbda-kup6s

# Infrastructure bucket
metadata:
  name: backup-etcd-kup6s

# Another application bucket
metadata:
  name: uploads-myapp-production-kup6s

Rule: Always suffix bucket names with -kup6s to ensure global uniqueness and avoid collisions.

Error Example:

Error: creating S3 Bucket (my-bucket): BucketAlreadyExists:
The requested bucket name is not available. The bucket namespace is shared by
all users of the system. Please select a different name and try again.

Known Limitations¶

Tagging Not Supported¶

Issue: Hetzner S3 doesn’t implement the PutBucketTagging API (returns HTTP 501 Not Implemented).

Solution: Use managementPolicies to skip Update operations:

apiVersion: s3.aws.upbound.io/v1beta1
kind: Bucket
metadata:
  name: data-myapp-kup6s  # Following naming convention: LOCALPART-NAMESPACE-kup6s
spec:
  deletionPolicy: Delete
  managementPolicies:
    - Observe  # Monitor bucket state
    - Create   # Create bucket
    - Delete   # Delete bucket
    # Skip Update/LateInitialize to avoid tagging operations
  forProvider:
    region: fsn1
  providerConfigRef:
    name: hetzner-s3

Result with managementPolicies:

Status: SYNCED=True, READY=True (clean status)
No tagging errors
Bucket fully functional

Result WITHOUT managementPolicies:

Status: SYNCED=False, READY=True
Error: operation error S3: PutBucketTagging, StatusCode: 501, NotImplemented
Bucket functional but status unclean

Fix existing buckets:

kubectl patch bucket.s3.aws.upbound.io <bucket-name> \
  -p '{"spec":{"managementPolicies":["Observe","Create","Delete"]}}' --type=merge

AWS-Specific Features Not Supported¶

The following AWS S3 features are not available in Hetzner Object Storage:

Bucket tagging (PutBucketTagging, GetBucketTagging)
Server-side encryption configuration (SSE-KMS)
Object Lock (WORM)
S3 Lifecycle rules
Bucket replication
Bucket metrics
Bucket analytics
S3 Inventory
S3 Select

Supported Features:

Basic bucket operations (create, delete, list)
Object operations (put, get, delete, list)
Multipart uploads
Bucket versioning
CORS configuration
Bucket policies (limited)
Pre-signed URLs

Troubleshooting¶

Error: “does not belong to a known partition”¶

Full Error:

cannot initialize the Terraform plugin SDK async external client:
cannot get terraform setup: cannot configure AWS partition:
managed resource region "fsn1" does not belong to a known partition

Cause: Missing or incorrect ProviderConfig fields

Solution: Ensure ProviderConfig has:

skip_region_validation: true
partitionId: aws

Error: “lookup s3.fsn1.amazonaws.com: no such host”¶

Full Error:

request send failed, Put "https://s3.fsn1.amazonaws.com/bucket-name":
dial tcp: lookup s3.fsn1.amazonaws.com on 10.43.0.10:53: no such host

Cause: Custom endpoint not applied to S3 service

Solution: Add services: [s3] to endpoint configuration

Critical: This is the most common issue - the services field is required

Error: “InvalidAccessKeyId: The AWS Access Key Id you provided does not exist”¶

Cause: Invalid or expired S3 credentials

Solution:

Verify credentials in Hetzner Cloud Console (Object Storage → Access Keys)
Ensure credentials match those in .env file
Regenerate credentials if needed
Run tofu apply to update secret in cluster
Restart provider pod: kubectl delete pod -n crossplane-system -l pkg.crossplane.io/provider=provider-aws-s3

Error: “static credentials are empty”¶

Cause: Secret in wrong format (JSON instead of INI)

Solution: Secret must use INI format:

[default]
aws_access_key_id = xxx
aws_secret_access_key = yyy

Not JSON format:

{"aws_access_key_id":"xxx","aws_secret_access_key":"yyy"}

Updating the Configuration¶

Modify ProviderConfig¶

Edit infrastructure template:

nano kube-hetzner/extra-manifests/50-B-crossplane-provider-s3.yaml.tpl

Apply changes (use the mandatory apply script):

cd kube-hetzner
bash scripts/apply-and-configure-longhorn.sh

Restart provider pod (optional, for immediate effect):

kubectl delete pod -n crossplane-system -l pkg.crossplane.io/provider=provider-aws-s3

Rotate S3 Credentials¶

Generate new credentials in Hetzner Cloud Console
- Navigate to: Object Storage → Access Keys
- Click: Create Access Key
- Copy: Access Key ID and Secret Access Key

Update .env file:

TF_VAR_hetzner_s3_access_key="<NEW_ACCESS_KEY>"
TF_VAR_hetzner_s3_secret_key="<NEW_SECRET_KEY>"

Apply changes:
```
cd kube-hetzner
source .env
tofu apply
```

Restart provider pod:

kubectl delete pod -n crossplane-system -l pkg.crossplane.io/provider=provider-aws-s3

Verify: New buckets should create successfully

Version Information¶

Provider: upbound/provider-aws-s3 Version: v2.1.1 (as of 2025-10-25) API Version: aws.upbound.io/v1beta1 Installed By: Crossplane (infrastructure-managed)