AWS Certified Solutions Architect – Professional SAP-C01 – Question342

A user wants to create a public subnet in VPC and launch an EC2 instance within it. The user has not selected the option to assign a public IP address while launching the instance.
Which of the below mentioned statements is true with respect to this scenario?

A. The instance will always have a public DNS attached to the instance by default
B. The user would need to create a default route to IGW in subnet's route table and then attach an elastic IP to the instance to connect from the internet
C. The user can directly attach an elastic IP to the instance
D. The instance will never launch if the public IP is not assigned

Correct Answer: B

Explanation:

Explanation: A Virtual Private Cloud (VPC) is a virtual network dedicated to the user’s AWS account. A user can create a subnet with VPC and launch instances inside that subnet. When the user is launching an instance he needs to select an option which attaches a public IP to the instance. If the user has not selected the option to attach the public IP, then it will only have a private IP when launched. The user cannot connect to the instance from the internet. If the user wants an elastic IP to connect to the instance from the internet, he should create an internet gateway and assign an elastic IP to instance.
Reference:
http://docs.aws.amazon.com/AmazonVPC/latest/GettingStartedGuide/Lau…