How can I add IPv6 connectivity to a running EC2 instance ?

Question

I set up an EC2 instance some years ago, running CentOS 7.
I've lost my notes, or rather, they're on a computer that's now behind NAT that I can't get to from here.
I'm a lot more familiar with CentOS on real hardware than I am with  AWS. I don't remember it being this complicated - I think I just configured a package fairly quickly, started it, logged in with SSH and never touched the consoles again.

I want to enable IPv6 connectivity. As I understand it, my instance has a virtual ethernet card instead of a real one, so I need to use the console to provision IPv6 upstream of that, then in CentOS configure the system to use it for IPv6.

I have been through many console pages and documents with only limited success.

Answer

Hello.

As you know, to set up IPv6 with the AWS management console, you need to associate IPv6 with the VPC where EC2 is running and attach it to EC2.  
You can configure IPv6 for VPC and EC2 by following the steps in the document below.  
https://docs.aws.amazon.com/vpc/latest/userguide/vpc-migrate-ipv6.html

After configuration, you may need to enable IPv6 on the network interface on the EC2 OS.  
https://www.gyrocode.com/articles/how-to-configure-ipv6-on-amazon-ec2-instance-running-centos-7/

How can I add IPv6 connectivity to a running EC2 instance ?

Relevant content