Using c5d EC2 AWS instances in terraform-aws-eks module

c5d EC2 instances have internal NVMe storage. To use the advantage of NVMe internal disks in the terraform-aws-eks module as a Launch Template for the Autoscaler Groups the support was added in the following PRs:

In case you need a cost-effective AWS instance with high throughput and amount of IOPS this should be a good choice for EKS instances. A drawback could be instance has a fixed disk size of the NVMe disk.

More information about c5 instances with local NVMe storage can be found here:

List of supported AWS instances and other options in terraform-aws-eks module is defined by AWS CLI Reference in section option parameter ‘instance-type’ –

Port 80 is being used by SYSTEM (PID 4)

If your application can’t start anymore on port 80 or you see HTTP Error 404. The requested resource is not found. it looks like http.sys placed reservation of port 80 and your application can’t start anymore.

In most cases this could happen after Windows Update or SCCM agent pushing updates and the agent won’t do the proper cleanup of reserved HTTP namespace.

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Kubernetes pod-network-cidr and service-cidr can’t overlap with intranet network ranges

If you initialize Kubernetes cluster with kubeadm check with the network team if the ranges you provide to kubeadm with –pod-network-cidr and –service-cidr does not overlap with intranet network ranges. Otherwise, pods/services won’t operate well and you might see anomalies in your Kubernetes environment.

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