0
votes

I am creating a Terraform script which creates a IAM role to be assumbed by EC2 instance via Launch Template. I have a simple lambda function (boto3/python) that creates/launches the EC2 instance using the Launch Template. However, I am getting this error when I run the lambda function:

"errorMessage": "An error occurred (InvalidParameterValue) when calling the RunInstances operation:
Value (arn:aws:iam::xxx:instance-profile/RigstopgapInstanceProfile) for parameter iamInstanceProfile.name is invalid. Invalid IAM Instance Profile name",
  "errorType": "ClientError",

My terraform code is this one:

resource "aws_launch_template" "rig_stopgap" {
  name          = "rig_stopgap"
  image_id      = var.ami_image
  instance_type = var.instance_type

  iam_instance_profile {
    name = aws_iam_instance_profile.rig_stopgap.arn
  }
  ...
}

resource "aws_iam_instance_profile" "rig_stopgap" {
  name = "RigstopgapInstanceProfile"
  role = aws_iam_role.rigs_stopgap_ec2.name
}

# EC2 "Trust relationships" policy (necessary to allow the instance to assume a role)
data "aws_iam_policy_document" "trust_relationships_ec2_policy" {
  statement {
    actions = ["sts:AssumeRole"]
    principals {
      type        = "Service"
      identifiers = ["ec2.amazonaws.com"]
    }
  }
}

# EC2 main policy
resource "aws_iam_policy" "rigs_stopgap_ec2_policy" {
  name        = "RigsStopgapPolicy"
  description = "Rigs Stopgap Policy allowing access to all of the necessary resources"

  policy = <<EOF
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Action": [
        "dynamodb:UpdateItem"
      ],
      "Effect": "Allow",
      "Resource": "${aws_dynamodb_table.rigs_stopgap.arn}"
    }
  ]
}
EOF
}

# Attach the ec2 policy 
resource "aws_iam_role_policy_attachment" "attach_ec2_instance_policy" {
  role       = aws_iam_role.rigs_stopgap_ec2.name
  policy_arn = aws_iam_policy.rigs_stopgap_ec2_policy.arn
}

resource "aws_iam_role" "rigs_stopgap_ec2" {
  name               = "RigsStopgapRole"
  assume_role_policy = data.aws_iam_policy_document.trust_relationships_ec2_policy.json
  tags               = var.common_tags
}

My Lambda code:

import boto3

ec2 = boto3.resource('ec2')
lt = {
    'LaunchTemplateName': 'rig_stopgap',
    'Version': '$Latest'
}


def handler(event, context):

    instances = ec2.create_instances(
        LaunchTemplate=lt,
        MinCount=1,
        MaxCount=1
    )

What am I missing?

Update: When I open the Launch Template in the AWS Console and navigate to the Instance Profile section it apparantly cannot find it: enter image description here

2

2 Answers

1
votes

I'm not familiar with Terraform, but it looks like you are providing an ARN when it is simply wanting a name:

  iam_instance_profile {
    name = aws_iam_instance_profile.rig_stopgap.arn
  }

Instead of providing the ARN, try just providing the name of the role.

1
votes

In your aws_launch_template there should be arn, not name, for iam_instance_profile:

 iam_instance_profile {
    arn = aws_iam_instance_profile.rig_stopgap.arn
  }