c12s-kubespray/docs/cilium.md

Cilium

Kube-proxy replacement with Cilium

Cilium can run without kube-proxy by setting cilium_kube_proxy_replacement to strict.

Without kube-proxy, cilium needs to know the address of the kube-apiserver and this must be set globally for all cilium components (agents and operators). Hence, in this configuration in Kubespray, Cilium will always contact the external loadbalancer (even from a node in the control plane) and if there is no external load balancer It will ignore any local load balancer deployed by Kubespray and only contacts the first master.

Cilium Operator

Unlike some operators, Cilium Operator does not exist for installation purposes.

The Cilium Operator is responsible for managing duties in the cluster which should logically be handled once for the entire cluster, rather than once for each node in the cluster.

Adding custom flags to the Cilium Operator

You can set additional cilium-operator container arguments using cilium_operator_custom_args. This is an advanced option, and you should only use it if you know what you are doing.

Accepts an array or a string.

cilium_operator_custom_args: ["--foo=bar", "--baz=qux"]

or

cilium_operator_custom_args: "--foo=bar"

You do not need to add a custom flag to enable debugging. Instead, feel free to use the CILIUM_DEBUG variable.

Adding extra volumes and mounting them

You can use cilium_operator_extra_volumes to add extra volumes to the Cilium Operator, and use cilium_operator_extra_volume_mounts to mount those volumes. This is an advanced option, and you should only use it if you know what you are doing.

cilium_operator_extra_volumes:
  - configMap:
      name: foo
    name: foo-mount-path

cilium_operator_extra_volume_mounts:
  - mountPath: /tmp/foo/bar
    name: foo-mount-path
    readOnly: true

Choose Cilium version

cilium_version: v1.11.3

Add variable to config

Use following variables:

Example:

cilium_config_extra_vars:
  enable-endpoint-routes: true

Change Identity Allocation Mode

Cilium assigns an identity for each endpoint. This identity is used to enforce basic connectivity between endpoints.

Cilium currently supports two different identity allocation modes:

• "crd" stores identities in kubernetes as CRDs (custom resource definition).
  • These can be queried with kubectl get ciliumid
• "kvstore" stores identities in an etcd kvstore.

Enable Transparent Encryption

Cilium supports the transparent encryption of Cilium-managed host traffic and traffic between Cilium-managed endpoints either using IPsec or Wireguard.

Wireguard option is only available in Cilium 1.10.0 and newer.

IPsec Encryption

For further information, make sure to check the official Cilium documentation.

To enable IPsec encryption, you just need to set three variables.

cilium_encryption_enabled: true
cilium_encryption_type: "ipsec"

The third variable is cilium_ipsec_key. You need to create a secret key string for this variable. Kubespray does not automate this process. Cilium documentation currently recommends creating a key using the following command:

echo "3 rfc4106(gcm(aes)) $(echo $(dd if=/dev/urandom count=20 bs=1 2> /dev/null | xxd -p -c 64)) 128"

Note that Kubespray handles secret creation. So you only need to pass the key as the cilium_ipsec_key variable.

Wireguard Encryption

For further information, make sure to check the official Cilium documentation.

To enable Wireguard encryption, you just need to set two variables.

cilium_encryption_enabled: true
cilium_encryption_type: "wireguard"

Kubespray currently supports Linux distributions with Wireguard Kernel mode on Linux 5.6 and newer.

Install Cilium Hubble

k8s-net-cilium.yml:

cilium_enable_hubble: true ## enable support hubble in cilium
cilium_hubble_install: true ## install hubble-relay, hubble-ui
cilium_hubble_tls_generate: true ## install hubble-certgen and generate certificates

To validate that Hubble UI is properly configured, set up a port forwarding for hubble-ui service:

kubectl port-forward -n kube-system svc/hubble-ui 12000:80

and then open http://localhost:12000/.

Hubble metrics

cilium_enable_hubble_metrics: true
cilium_hubble_metrics:
  - dns
  - drop
  - tcp
  - flow
  - icmp
  - http

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