Amazon Web Services SAA-C03 Exam With Confidence Using Practice Dumps

Why Option B is Correct:

AWS WAF: Provides a simple way to create geographic match rules to block or allow traffic based on country IP ranges.

Least Operational Overhead: Attaching the WAF rule to the ALB ensures centralized control without modifying ACLs or instance firewalls.

Why Other Options Are Not Ideal:

Option A: Network ACLs operate at the subnet level and can become complex to manage for dynamic or evolving IP ranges.

Option C: Managing IP-based rules in security groups and ACLs lacks scalability and does not provide country-based filtering.

Option D: Configuring host-based firewalls increases operational overhead and does not leverage AWS-managed solutions.

AWS References:

AWS WAF Geomatch:AWS Documentation - WAF Geomatch

This solution provides the most secure access for external support engineers with the least exposure to potential security risks.

AWS Systems Manager (SSM) and Session Manager: Systems Manager Session Manager allows secure and auditable access to EC2 instances without the need to open inbound SSH ports or manage SSH keys. This reduces the attack surface significantly. The SSM Agent must be installed and configured on all instances, and the instances must have an instance profile with the necessary IAM permissions to connect to Systems Manager.

IAM Identity Center: IAM Identity Center provides centralized management of access to the AWS Management Console for external support engineers. By using IAM Identity Center, youcan control console access securely and ensure that external engineers have the appropriate permissions based on their roles.

Why Not Other Options?:

Option B (Local IAM user credentials): This approach is less secure because it involves managing local IAM user credentials and does not leverage the centralized management and security benefits of IAM Identity Center.

Option C (Security group with SSH access): Allowing SSH access opens up the infrastructure to potential security risks, even when restricted by IP addresses. It also requires managing SSH keys, which can be cumbersome and less secure.

Option D (Bastion host): While a bastion host can secure SSH access, it still requires managing SSH keys and opening ports. This approach is less secure and more operationally intensive compared to using Session Manager.

AWS References:

AWS Systems Manager Session Manager- Documentation on using Session Manager for secure instance access.

AWS IAM Identity Center- Overview of IAM Identity Center and its capabilities for managing user access.

Explanation (AWS Docs):

To allow private subnets to access the internet, deploy NAT gateways in a public subnet in each AZ for high availability. NAT instances are less scalable and less fault-tolerant.

“To create a highly available architecture, create a NAT gateway in each Availability Zone and configure your routing to use it.”

— NAT Gateway Overview