Is there a way to get the EC2 instances which belongs to an EKS cluster via AWS SDK library?

Question

I created a function that will generate reports corresponding to vulnerabilities found in EC2 instances and push them to a bucket in S3 by using the SDK library for Node.js, I'm currently using the Inspector2 module for that task and everything works properly. But now I need to create a filter in the reports to match only the EC2 instances that belongs to EKS clusters. So I decided to take a look at the EKS client module but neither the describeCluster nor the listClusters functions give information about the instances included in the different clusters. So after investigating I found a function in the EKS client that retrieves the node groups corresponding to an EKS cluster and its autoscaling groups associated, and with that information I think I can use the Auto-scaling client to describe the auto scaling groups and get information about the instances which belongs to those groups. But I'm not sure if that would work and I think putting all that pieces together will cost much time. So if someone knows about a better way to achieve this kind of task I would appreciate so much. Thanks in advance.

Answer 1

If you use eksctl to provision your clusters, you can interrogate the instance's tags to get the cluster they belong to. Instances provisioned by eksctl will include the keys kubernetes.io/cluster/<CLUSTER_NAME> and eks:cluster-name (the value of this key is set to the CLUSTER_NAME).