Generic Veth Chaining
The generic veth chaining plugin enables CNI chaining on top of any CNI plugin that is using a veth device model. The majority of CNI plugins use such a model.
Note
Some advanced Cilium features may be limited when chaining with other CNI plugins, such as:
Validate that the current CNI plugin is using veth
Log into one of the worker nodes using SSH
Run
ip -d link
to list all network devices on the node. You should be able spot network devices representing the pods running on that node.A network device might look something like this:
103: lxcb3901b7f9c02@if102: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000 link/ether 3a:39:92:17:75:6f brd ff:ff:ff:ff:ff:ff link-netnsid 18 promiscuity 0 veth addrgenmode eui64 numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
The
veth
keyword on line 3 indicates that the network device type is virtual ethernet.
If the CNI plugin you are chaining with is currently not using veth then the
generic-veth
plugin is not suitable. In that case, a full CNI chaining
plugin is required which understands the device model of the underlying plugin.
Writing such a plugin is trivial, contact us on Cilium Slack for more
details.
Create a CNI configuration to define your chaining configuration
Create a chaining.yaml
file based on the following template to specify the
desired CNI chaining configuration:
apiVersion: v1
kind: ConfigMap
metadata:
name: cni-configuration
namespace: kube-system
data:
cni-config: |-
{
"name": "generic-veth",
"cniVersion": "0.3.1",
"plugins": [
{
"type": "XXX",
[...]
},
{
"type": "cilium-cni",
"chaining-mode": "generic-veth"
}
]
}
Deploy the ConfigMap:
kubectl apply -f chaining.yaml
Deploy Cilium with the portmap plugin enabled
Download the Cilium release tarball and change to the kubernetes install directory:
curl -LO https://github.com/cilium/cilium/archive/main.tar.gz tar xzf main.tar.gz cd cilium-main/install/kubernetes
Deploy Cilium release via Helm:
helm install cilium ./cilium \ --namespace=kube-system \ --set cni.chainingMode=generic-veth \ --set cni.customConf=true \ --set cni.configMap=cni-configuration \ --set routingMode=native \ --set enableIPv4Masquerade=false