TL;DR

App can not fetch required info in ipv6 only due to reliance on metadata service - caused by #996

Expected behavior

I can run the controller and csi-node on ipv6 only environments.
Required information should be tried from multiple sources.

Observed behavior

Controller and node crash on ipv6 only pods due to missing info about location and server-id

Minimal working example

Create a single node cluster with ipv6 on hcloud

Log output

Logs:

time=2025-11-07T21:28:13.441Z level=DEBUG source=/home/runner/work/csi-driver/csi-driver/internal/metrics/metrics.go:36 msg="registering metrics with registry"
time=2025-11-07T21:28:13.441Z level=DEBUG source=/home/runner/work/csi-driver/csi-driver/internal/metrics/metrics.go:43 msg="registered metrics"
time=2025-11-07T21:28:13.441Z level=DEBUG source=/home/runner/work/csi-driver/csi-driver/internal/metrics/metrics.go:69 msg="starting prometheus http server" addr=0.0.0.0:9189
time=2025-11-07T21:28:13.442Z level=WARN source=/home/runner/work/csi-driver/csi-driver/cmd/main.go:51 msg="unable to connect to the metadata service"
time=2025-11-07T21:28:13.442Z level=ERROR source=/home/runner/work/csi-driver/csi-driver/cmd/main.go:56 msg="could not determine default volume location" error="HCLOUD_VOLUME_DEFAULT_LOCATION not set and not running on a cloud server"
stream closed: EOF for kube-system/hcloud-csi-controller-55d6888b97-mn2fh (hcloud-csi-driver)

Additional information

Previously the app used multiple sources to get the required information about location and server ID. Now it only relies on hardcoded information or the (ipv4 only) metadata-service.

The app should try to fetch all needed information with fallbacks in place. The suggested order:

• Explicit configuration via ENV or Conf-File
• Query the metadata-service
• Query the Hetzner-API
• Query the Kubernetes Node-API (via labels set by the ccm)

The first three steps were already used before merging the node and controller. In the file https://github.com/hetznercloud/csi-driver/blame/main/internal/app/app.go is still the old code to query by Hetzner-API as a fallback