How do you debug Helm charts and troubleshoot rendering issues?

Helm provides multiple debugging tools to identify issues before and after deployment.

Template rendering debugging:

• helm template RELEASE_NAME CHART_PATH - Renders templates without installing, shows exact Kubernetes YAML that would be applied
• helm template --debug - Shows template execution details and any Go template errors
• helm get manifest RELEASE_NAME - Shows what was actually deployed for an existing release
• helm get values RELEASE_NAME - Shows values used for a release (including defaults and overrides)
• helm get notes RELEASE_NAME - Shows NOTES.txt output (helpful for connection info)
• helm get all RELEASE_NAME - Combined output of everything

Syntax validation: helm lint CHART_PATH validates Chart.yaml, values.yaml, and template syntax. Returns warnings and errors with line numbers.

Dry run with diff: helm upgrade --install RELEASE CHART --dry-run --debug shows what would change without applying. Add --dry-run=server (Helm v3.11+) for server-side validation.

Common debugging patterns:

• Add {{- fail "Debug: value is " .Values.somevalue }} to stop rendering and print values
• Use {{ .Values | toYaml | nindent 2 }} to dump all values during debugging
• Set HELM_DEBUG=1 environment variable for verbose client logs
• Check release status: helm status RELEASE_NAME --show-resources
• View failed resource creation: kubectl get events --all-namespaces | grep RELEASE_NAME

Remote debugging: For CI failures, use helm history RELEASE_NAME to find problematic revision, then helm get values --revision N to see what changed.