AWS Certified SysOps Administrator – Associate (legacy) — Question 702

A SysOps Administrator receives a connection timeout error when attempting to connect to an Amazon EC2 instance from a home network using SSH. The
Administrator was able to connect to this EC2 instance using from their office network in the past.
What caused the connection to time out?

Answer options

• A. The IAM role associated with the EC2 instance does not allow SSH connections from the home network.
• B. The public key used by SSH located on the Administrator's server does not have the required permissions.
• C. The route table contains a route that sends 0.0.0.0/0 to the internet gateway for the VPC.
• D. The security group is not allowing inbound traffic from the home network on the SSH port.

Correct answer: D

Explanation

A connection timeout indicates that the network traffic is being blocked or dropped, which typically occurs when the security group does not allow inbound SSH traffic (port 22) from the client's current IP address. Incorrect SSH key permissions would result in a 'Permission denied' error rather than a timeout, and IAM roles do not control network-level access. A route directing traffic to the internet gateway is necessary for internet connectivity, so its presence would facilitate rather than block the connection.