249 lines
8.2 KiB
Markdown
249 lines
8.2 KiB
Markdown
# Cilium
|
||
|
||
## IP Address Management (IPAM)
|
||
|
||
IP Address Management (IPAM) is responsible for the allocation and management of IP addresses used by network endpoints (container and others) managed by Cilium. The default mode is "Cluster Scope".
|
||
|
||
You can set the following parameters, for example: cluster-pool, kubernetes:
|
||
|
||
```yml
|
||
cilium_ipam_mode: cluster-pool
|
||
```
|
||
|
||
### Set the cluster Pod CIDRs
|
||
|
||
Cluster Pod CIDRs use the kube_pods_subnet value by default.
|
||
If your node network is in the same range you will lose connectivity to other nodes.
|
||
Defaults to kube_pods_subnet if not set.
|
||
You can set the following parameters:
|
||
|
||
```yml
|
||
cilium_pool_cidr: 10.233.64.0/18
|
||
```
|
||
|
||
When cilium_enable_ipv6 is used. Defaults to kube_pods_subnet_ipv6 if not set.
|
||
you need to set the IPV6 value:
|
||
|
||
```yml
|
||
cilium_pool_cidr_ipv6: fd85:ee78:d8a6:8607::1:0000/112
|
||
```
|
||
|
||
### Set the Pod CIDR size of a node
|
||
|
||
When cilium IPAM uses the "Cluster Scope" mode, it will pre-allocate a segment of IP to each node,
|
||
schedule the Pod to this node, and then allocate IP from here. cilium_pool_mask_size Specifies
|
||
the size allocated from cluster Pod CIDR to node.ipam.podCIDRs.
|
||
Defaults to kube_network_node_prefix if not set.
|
||
|
||
```yml
|
||
cilium_pool_mask_size: "24"
|
||
```
|
||
|
||
cilium_pool_mask_size Specifies the size allocated to node.ipam.podCIDRs from cluster Pod IPV6 CIDR. Defaults to kube_network_node_prefix_ipv6 if not set.
|
||
|
||
```yml
|
||
cilium_pool_mask_size_ipv6: "120"
|
||
```
|
||
|
||
## 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).
|
||
We can only use the localhost apiserver loadbalancer in this mode
|
||
whenever it uses the same port as the kube-apiserver (by default it does).
|
||
|
||
## 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: v1.15.4
|
||
```
|
||
|
||
## 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 $(dd if=/dev/urandom count=20 bs=1 2> /dev/null | xxd -p -c 64)) 128"
|
||
```
|
||
|
||
Note that Kubespray handles secret creation. So you only need to pass the key as the `cilium_ipsec_key` variable, base64 encoded:
|
||
|
||
```shell
|
||
echo "cilium_ipsec_key: "$(echo -n "3 rfc4106(gcm(aes)) $(echo $(dd if=/dev/urandom count=20 bs=1 2> /dev/null | xxd -p -c 64)) 128" | base64 -w0)
|
||
```
|
||
|
||
### 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.
|
||
|
||
## Bandwidth Manager
|
||
|
||
Cilium’s bandwidth manager supports the kubernetes.io/egress-bandwidth Pod annotation.
|
||
|
||
Bandwidth enforcement currently does not work in combination with L7 Cilium Network Policies.
|
||
In case they select the Pod at egress, then the bandwidth enforcement will be disabled for those Pods.
|
||
|
||
Bandwidth Manager requires a v5.1.x or more recent Linux kernel.
|
||
|
||
For further information, make sure to check the official [Cilium documentation.](https://docs.cilium.io/en/v1.12/gettingstarted/bandwidth-manager/)
|
||
|
||
To use this function, set the following parameters
|
||
|
||
```yml
|
||
cilium_enable_bandwidth_manager: true
|
||
```
|
||
|
||
## 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.
|