No way to specify Cilium native routing CIDR except via helm values file?

[codepainters]

I've tried creating a cluster with Cilium native routuing mode, unfortunately it leads to a cilium pod crash loop:

time="2026-02-20T09:42:41.876171907Z" level=fatal msg="invalid daemon configuration: native routing cidr must be configured with option --ipv4-native-routing-cidr in combination with --enable-ipv4=true --enable-ipv4-masquerade=true --enable-ip-masq-agent=false --routing-mode=native --ipam=kubernetes" subsys=daemon

Indeed, I can't find any code reference including ipv4NativeRoutingCIDR while setting the routing mode is possible:

hetzner-k3s/src/kubernetes/software/cilium.cr

Lines 106 to 121 in fb1ac72

	template_vars = {
	encryption_enabled: settings.networking.cni.encryption,
	encryption_type: cilium_config.encryption_type || DEFAULT_ENCRYPTION_TYPE,
	routing_mode: cilium_config.routing_mode || DEFAULT_ROUTING_MODE,
	tunnel_protocol: cilium_config.tunnel_protocol || DEFAULT_TUNNEL_PROTOCOL,
	hubble_enabled: cilium_config.hubble_enabled || true,
	hubble_metrics: build_hubble_metrics_array(cilium_config.hubble_metrics),
	hubble_relay_enabled: cilium_config.hubble_relay_enabled || true,
	hubble_ui_enabled: cilium_config.hubble_ui_enabled || true,
	k8s_service_host: cilium_config.k8s_service_host || DEFAULT_K8S_SERVICE_HOST,
	k8s_service_port: cilium_config.k8s_service_port || DEFAULT_K8S_SERVICE_PORT,
	operator_replicas: cilium_config.operator_replicas || DEFAULT_OPERATOR_REPLICAS,
	operator_memory_request: cilium_config.operator_memory_request || DEFAULT_OPERATOR_MEMORY_REQUEST,
	agent_memory_request: cilium_config.agent_memory_request || DEFAULT_AGENT_MEMORY_REQUEST,
	egress_gateway_enabled: settings.networking.cni.cilium_egress_gateway,
	}

Perhaps it is worth adding?

Also - is there any way to render the helm values template for review / customization ?

[vitobotta]

Hi, you can specify your own custom values for the Helm chart wit the networking.cni.cilium.helm_values_path setting. I'll close this one for now, but feel free to reopen if you still need help even after that.

[vitobotta]

This is documened in the cluster config example btw. https://vitobotta.github.io/hetzner-k3s/Creating_a_cluster/?h=helm_values_path#configuration-file

[codepainters]

Hi, you can specify your own custom values for the Helm chart wit the networking.cni.cilium.helm_values_path setting. I'll close this one for now, but feel free to reopen if you still need help even after that.

I know, and I do exactly that now - but on the other hand routing_mode can be set directly, without custom helm values file. Yet if setting native routing mode without setting ipv4NativeRoutingCIDR is of little value. If setting routing mode without heml values file is possible, so should be native routing cidr, imho.

[vitobotta]

I think I am going to remove the settings from there and just require using a file (or offer a file with the current default) since it's more flexible.

[codepainters]

Fair enough - given the amount of Cilium options, it's very subjective what's worth exposing.