Launching and Managing EC2 Instances

Example launching an EC2 Instance

• Instance Name: MyFirstInstance
• AMI Selection: Amazon Linux
• Instance Type: t2.micro
• Key Pair:
  • Creation of a new key pair named DemoKeyPair
  • Key type: RSA pem
• Network Settings:
  • Creation of a new security group named AWSSSH
  • SSH allowed on port 22 from anywhere
• Storage: Default settings
• Instance Launch: Successfully launched the instance

Connecting to the EC2 Instance

• Method 1: SSH
  • Change permissions of the key pair file: chmod 400 DemoKeyPair.pem
  • Connect via SSH: ssh -i DemoKeyPair.pem ec2-user@<Public-IP>
  • Test command: echo "hello world"
• Method 2: EC2 Instance Connect
  • Use the EC2 console to connect with EC2 Instance Connect
  • Username: ec2-user
  • Test command execution within the instance

Changing the EC2 Instance Type

• Prerequisite: Instance must be EBS-backed
• Steps:
  1. Stop the instance
  2. Change the instance type (e.g., from t2.micro to t2.small for more RAM and CPU)
  3. Start the instance again
• Example:
  • Create a file hello.txt with content "hello"
  • Check available memory with free -m (Original: 993 MB RAM)
  • Stop the instance
  • Change instance type to t2.small
  • Start the instance
  • Reconnect and verify:
    • File hello.txt persists
    • Available memory increased to 1991 MB RAM
• Note: Changing to a non-free tier instance type will incur charges. Remember to revert back to t2.micro to stay within the free tier.

Key Takeaways

• Ensure your instance is EBS-backed to retain data after stopping and starting.
• Changing the instance type allows you to scale the instance's resources according to your needs.