redshift-error.sh

cat <<EOM > /tmp/assume-role-policy.json
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Service": [
          "redshift.amazonaws.com"
        ]
      },
      "Action": [
        "sts:AssumeRole"
      ]
    }
  ]
}
EOM

role1_arn=$(
  aws iam create-role \
    --role-name test_role_1 \
    --assume-role-policy-document file:///tmp/assume-role-policy.json |
  jq -r '.Role.Arn'
)

role2_arn=$(
  aws iam create-role \
    --role-name test_role_2 \
    --path '/mypath/' \
    --assume-role-policy-document file:///tmp/assume-role-policy.json |
  jq -r '.Role.Arn'
)

# This produces:
# An error occurred (InvalidParameterValue) when calling the CreateCluster
# operation: Invalid IAM Role ARN format:
# arn:aws:iam::[REDACTED]:role/mypath/test_role_2
aws redshift create-cluster \
  --cluster-identifier my-test-cluster \
  --cluster-type single-node \
  --node-type dc1.large \
  --master-username test \
  --master-user-password Test0123 \
  --iam-roles "$role2_arn"

# This succeeds:
aws redshift create-cluster \
  --cluster-identifier my-test-cluster \
  --cluster-type single-node \
  --node-type dc1.large \
  --master-username test \
  --master-user-password Test0123 \
  --iam-roles "$role1_arn"