[Feature] Bare cluster check is too strict, no room for custom CNIs and kube-proxy-less deployments

[avoidik]

What feature/behavior/change do you want?

Perhaps I'm doing something wrong, but at the moment I am not able to deploy custom CNIs using eksctl due to the fact that the aws-vpc-cni addon is a compulsory addon. Nevertheless, I believe this is not a hard requirement.

I would like to suggest to demote the following showstopper error into a warning:

fields nodeGroups, managedNodeGroups, fargateProfiles, karpenter, gitops, iam.serviceAccounts, and iam.podIdentityAssociations are not supported during cluster creation in a cluster without VPC CNI if Auto Mode is disabled; please remove these fields and add them back after cluster creation is successful

The error stated that it's unsupported configuration, while in reality it works, and actually it's a part of the CNI deployment pattern, including Cilium.

Why do you want this feature?

To be able to deploy CNIs without the kube-proxy and aws-vpc-cni addons. I want to be able to control myself what to deploy in terms of CNIs.

[github-actions]

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[avoidik]

Relevant block of code.

https://github.com/eksctl-io/eksctl/blob/v0.214.0/pkg/ctl/cmdutils/configfile.go#L489-L502

Changing return errors.New to logger.Warning(...); return nil works just fine, in this case a CNI could be installed manually.

[naclonts]

Hi @avoidik, do you mind giving an example of what you're trying to install? Looking to understand your use case here to see what behavior would make sense.

[avoidik]

hello,

here's an example:

apiVersion: eksctl.io/v1alpha5
kind: ClusterConfig
metadata:
  name: galaxy
  region: eu-central-1
  version: "1.33"
iam:
  withOIDC: true
addonsConfig:
  disableDefaultAddons: true
addons:
  - name: coredns
  - name: aws-ebs-csi-driver
managedNodeGroups:
  - name: workers
    instanceType: m5.xlarge
    desiredCapacity: 3
    amiFamily: AmazonLinux2023
    privateNetworking: true