[Feature] Add column for Private IPv4 addresses per ENI

[fincd-aws]

I have to constantly match up this chart with the one that only contains number of ENIs and number of Private IPv4 Addresses per ENI for each instance type: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-eni.html

I look at this because EKS VPC CNI assigned a "full ENI worth" of IPs, filling the primary ENI when new instances start. The size of this cache of IPs is important for pods to start quickly, and also can run the subnet out of IPs.

Picking an instance type with all three resources (CPU/Memory/IPs-per-ENI) in the most accurate ratio is very useful.

[EverettBerry]

@fincd-aws so would this be a matter of just dividing the max IPs column by the max ENIs column?

[fincd-aws]

Yes, that is the right math, though I don't know what data source you have that lists total IPs.

The AWS EC2 API and AWS CLI aws ec2 describe-instance-types output is already in the format I'm looking for:

"Ipv4AddressesPerInterface": 2,

Maybe you are doing the multiplication on your end?

[EverettBerry]

Yep that's right but perhaps we should not multiply it because I actually don't know how useful the total is. https://github.com/vantage-sh/ec2instances.info/blob/85e0a1361ce36f4d0bf8b94af9c8caa3daee78c8/in/index.html.mako#L436