185 lines
6.2 KiB
Markdown
185 lines
6.2 KiB
Markdown
# 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.
|
|
|
|
```yml
|
|
cilium_operator_custom_args: ["--foo=bar", "--baz=qux"]
|
|
```
|
|
|
|
or
|
|
|
|
```yml
|
|
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.
|
|
|
|
```yml
|
|
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
|
|
|
|
```yml
|
|
cilium_version: v1.12.1
|
|
```
|
|
|
|
## Add variable to config
|
|
|
|
Use following variables:
|
|
|
|
Example:
|
|
|
|
```yml
|
|
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.](https://docs.cilium.io/en/stable/gettingstarted/encryption-ipsec/)
|
|
|
|
To enable IPsec encryption, you just need to set three variables.
|
|
|
|
```yml
|
|
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:
|
|
|
|
```shell
|
|
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.](https://docs.cilium.io/en/stable/gettingstarted/encryption-wireguard/)
|
|
|
|
To enable Wireguard encryption, you just need to set two variables.
|
|
|
|
```yml
|
|
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:
|
|
|
|
```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:
|
|
|
|
```shell script
|
|
kubectl port-forward -n kube-system svc/hubble-ui 12000:80
|
|
```
|
|
|
|
and then open [http://localhost:12000/](http://localhost:12000/).
|
|
|
|
## Hubble metrics
|
|
|
|
```yml
|
|
cilium_enable_hubble_metrics: true
|
|
cilium_hubble_metrics:
|
|
- dns
|
|
- drop
|
|
- tcp
|
|
- flow
|
|
- icmp
|
|
- http
|
|
```
|
|
|
|
[More](https://docs.cilium.io/en/v1.9/operations/metrics/#hubble-exported-metrics)
|
|
|
|
## Upgrade considerations
|
|
|
|
### Rolling-restart timeouts
|
|
|
|
Cilium relies on the kernel's BPF support, which is extremely fast at runtime but incurs a compilation penalty on initialization and update.
|
|
|
|
As a result, the Cilium DaemonSet pods can take a significant time to start, which scales with the number of nodes and endpoints in your cluster.
|
|
|
|
As part of cluster.yml, this DaemonSet is restarted, and Kubespray's [default timeouts for this operation](../roles/network_plugin/cilium/defaults/main.yml)
|
|
are not appropriate for large clusters.
|
|
|
|
This means that you will likely want to update these timeouts to a value more in-line with your cluster's number of nodes and their respective CPU performance.
|
|
This is configured by the following values:
|
|
|
|
```yaml
|
|
# Configure how long to wait for the Cilium DaemonSet to be ready again
|
|
cilium_rolling_restart_wait_retries_count: 30
|
|
cilium_rolling_restart_wait_retries_delay_seconds: 10
|
|
```
|
|
|
|
The total time allowed (count * delay) should be at least `($number_of_nodes_in_cluster * $cilium_pod_start_time)` for successful rolling updates. There are no
|
|
drawbacks to making it higher and giving yourself a time buffer to accommodate transient slowdowns.
|
|
|
|
Note: To find the `$cilium_pod_start_time` for your cluster, you can simply restart a Cilium pod on a node of your choice and look at how long it takes for it
|
|
to become ready.
|
|
|
|
Note 2: The default CPU requests/limits for Cilium pods is set to a very conservative 100m:500m which will likely yield very slow startup for Cilium pods. You
|
|
probably want to significantly increase the CPU limit specifically if short bursts of CPU from Cilium are acceptable to you.
|