[loki-helm-chart] Template Error: volumeAttributesClassName nested inside storageClass with block

[tico24]

There's appears to be a template bug in the ingester StatefulSet templates that causes a rendering error when storageClass is set and volumeAttributesClassName is defined in the persistence claims configuration.

Error Message

Error: template: loki/charts/loki/templates/ingester/statefulset-ingester-zone-b.yaml:237:17: executing "loki/charts/loki/templates/ingester/statefulset-ingester-zone-b.yaml" at <.volumeAttributesClassName>: can't evaluate field volumeAttributesClassName in type string

Root Cause

In the volumeClaimTemplates section, the volumeAttributesClassName field is nested inside the {{- with .storageClass }} block:

{{- with .storageClass }}
storageClassName: {{ if (eq "-" .) }}""{{ else }}{{ . }}{{ end }}
{{- with .volumeAttributesClassName }}
volumeAttributesClassName: {{ . }}
{{- end }}
{{- end }}

When {{- with .storageClass }} is entered, the context (.) becomes the value of storageClass (e.g., "gp3" string). When the inner {{- with .volumeAttributesClassName }} tries to access .volumeAttributesClassName, it's attempting to access this field on the string "gp3" instead of the parent claim object, causing the error.

Steps to Reproduce

1. Configure ingester persistence with a storageClass and volumeAttributesClassName:

ingester:
  zoneAwareReplication:
    enabled: true
  persistence:
    enabled: true
    claims:
      - name: data
        accessModes:
          - ReadWriteOnce
        size: 10Gi
        storageClass: gp3
        volumeAttributesClassName: null

2. Run helm template or deploy the chart
3. Observe the template rendering error

Environment

• Helm Chart Version: 6.49.0
• Loki Version: 3.6.3
• Kubernetes Version: 1.34

---

I imagine the fix is to just end the {{- with .storageClass }} prior to starting the {{- with .volumeAttributesClassName }} and to also add volumeAttributesClassName to the values.yaml.

[tico24]

I originally raised the issue here: grafana/helm-charts#4058

Because Loki helm charts seems to continually move around github and I'm no longer sure of the correct source.

[JStickler]

As of March 16, 2026, the Loki Helm Chart has been forked to the new Grafana-Community/helm-charts repo and is now being maintained by the Grafana Community and Grafana Champions. If this issue affects Grafana Enterprise Logs (GEL), please leave a comment here. Otherwise, if this is still an issue, please reopen your issue here here.