eks-external-snat
snat disabled (prefer)
work node in private subnet (LINK)

kubectl set env daemonset -n kube-system aws-node AWS_VPC_K8S_CNI_EXTERNALSNAT=true
snat enabled
work node in public subnet

kubectl set env daemonset -n kube-system aws-node AWS_VPC_K8S_CNI_EXTERNALSNAT=false
reference

https://broadcast.amazon.com/videos/388152