Troubleshooting: Unable to connect to the server: dial tcp x.x.x.x:443: i/o timeout

Problem:

I recently ran into a problem when trying to connect to an Amazon EKS cluster using the kubectl command. The error, “Unable to connect to the server: dial tcp x.x.x.x:443: i/o timeout” happened whenever I tried to connect to the cluster. For instance, if I ran the the kubectl get svc command the error would appear.

Solution:

The answer was to open port 443 inbound on each of the security groups related to the EKS cluster.