I created a new load balancer in aws. It has a a security group assigned to it that does not exist in my security group list, but one that existed long ago.
How do I associate the elb with an existing security group?
You can do this through the console:
From the EC2 Console go to "Load Balancers", select your Load Balancer from the list and click the "Security" tab.
You can then select one (or more) Security Group(s) from the list and click "Update Security Groups" when you're ready.
You can also do this through the CLI:
Associates one or more security groups with your load balancer in Amazon Virtual Private Cloud (Amazon VPC). The provided security group IDs will override any currently applied security groups.