Name: Things to keep in mind when starting with AWS
Rating: 4.9 (946 reviews)
Author: jorgetovar

Applications in the Cloud are reliable, and in some cases even cheaper than on-premises, but we all have made a lot of mistakes when started with AWS.

Cost Optimization

First and one of the most important tips to keep in mind:

Monitor your AWS costs by setting billing alerts & automate everything

CloudFormation template

---
AWSTemplateFormatVersion: "2010-09-09"
Description: "Simple budget example"
Parameters:
  Email:
    Type: String
    Default: email@example.com
    Description: Please enter the email address to which budget notifications should be addressed.
Resources:
  BasicBudget:
    Type: "AWS::Budgets::Budget"
    Properties:
      Budget:
        BudgetLimit:
          Amount: 10
          Unit: USD
        TimeUnit: MONTHLY
        BudgetType: COST
      NotificationsWithSubscribers:
        - Notification:
            NotificationType: ACTUAL
            ComparisonOperator: GREATER_THAN
            Threshold: 99
          Subscribers:
            - SubscriptionType: EMAIL
              Address: !Ref Email
        - Notification:
            NotificationType: ACTUAL
            ComparisonOperator: GREATER_THAN
            Threshold: 80
          Subscribers:
          - SubscriptionType: EMAIL
            Address: !Ref Email
Outputs:
  BudgetId:
    Value: !Ref BasicBudget

Tag everything

Performance Efficiency

Use Serverless Architectures as much as possible
Store no application state
Log useful information and enable traceability

Reliability

Scale-out is better in most of the cases

Security

Create an IAM user for your AWS account.
Enable MFA in all your AWS users
Grant roles to EC2, applications should not have AIM accounts
Assign privileges to groups and not directly to the users

Operational Excellence

Leverage Infrastructure as Code: Terraform, CDK or even CloudFormation
Make things easy to rollback