Uly.me

cloud engineer

aws

AWS Terraform Create Policy and Attach

Here’s the Terraform code that creates an AWS IAM policy and attaches it to an existing role (ROLENAME).

# CREDENTIALS
provider "aws" {
  shared_credentials_files = ["~/.aws/credentials"]
  shared_config_files      = ["~/.aws/config"]
  profile                  = "default"
  region                   = "us-east-1"
}
# CREATE POLICY
resource "aws_iam_policy" "s3-policy" {
    name        = "s3-policy"
    description = "Allow role to write to bucket"
    policy = "${file("policy.json")}"
}
# ATTACH POLICY TO ROLE
resource "aws_iam_role_policy_attachment" "s3-policy-attachment" {
  role       = "ROLENAME"
  policy_arn = aws_iam_policy.s3-policy.arn
}

Here’s the policy.json file.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "VisualEditor0",
            "Effect": "Allow",
            "Action": [
                "s3:PutObject",
                "s3:PutObjectAcl",
                "s3:ListBucket",
                "s3:GetBucketLocation",
                "s3:GetObject",
                "s3:GetObjectAcl",
                "s3:DeleteObject"
             ],
            "Resource":"arn:aws:s3:::your-bucket/*"
            }
        }
    ]
}

Change Hostname Amazon Linux

Here’s how to make a hostname stick on Amazon Linux.

Set preserve_hostname to true in /etc/cloud/cloud.cfg.

preserve_hostname: true

Set the hostname in /etc/sysconfig/network.

HOSTNAME=server.domain.com
NETWORKING=yes
NOZEROCONF=yes

Reboot the server to make sure hostname sticks after a reboot.

shutdown -r now

Login to confirm hostname sticks.

AWS RDS Enable Performance Insights

Here’s how to enable performance insights on a RDS instance.

Enable

aws rds modify-db-instance \
--db-instance-identifier sample-db-instance \
--enable-performance-insights \
--region us-east-1 \
--profile default

Disable

aws rds modify-db-instance \
--db-instance-identifier sample-db-instance \
--no-enable-performance-insights \
--region us-east-1 \
--profile default