How to Attach existing AWS IAM Roles to an EC2 instance?

Hey, I just wanted to know that If I had already some existed roles on AWS then Can I connect those roles to my ec2 instance which I am creating using Terraform And Same thing goes for policies like when we are creating any role using terraform then can I attach aws existing policy to it.

Yes. You just need to use their ARNs

@stuart-c Is there any docs regarding this thing ?

What sort of documentation are you looking for? If you look at the aws_instance documentation ( you can see the iam_instance_profile attribute expects the ARN of an instance profile to use for the EC2 instance.