You're automating the creation of multiple VCNs across different OCI regions using Cloud Shell scripting.
Which authentication method within Cloud Shell is best suited to programmatically authenticate with OCI, ensuring both security and scalability for this automation task?

• A. Leverage Instance Principals in conjunction with a dynamic group that includes your Cloud Shell session.
• B. Using the default Cloud Shell user and configuring the OCI CLI with API keys in a shell script.
• C. Using Resource Manager stack with Terraform to provision network resources including cross-region configurations, leveraging OCI Vault to handle the sensitive credentials used in Terraform scripts.
• D. Creating a dedicated IAM user for automation, generating API keys, storing the keys securely in Cloud Shell's persistent storage, and using them in the scripts.

Your security policy mandates that all communication between your compute instances in a private subnet and OCI Object Storage must be authenticated and authorized using IAM policies and not rely on public IP addresses. Which OCI networking feature is the most appropriate to satisfy this requirement?

• A. Public Subnet with an Internet Gateway and IAM rules.
• B. Public Subnet with a Network Firewall and IAM rules.
• C. Private Subnet with a NAT Gateway and IAM rules.
• D. Private Subnet with a Service Gateway and IAM rules.

You are using the OCI Application Load Balancer (ALB) for your web application. You want to implement a blue/green deployment strategy to minimize downtime during application updates. You have two backend sets: 'blue' (the current version) and 'green' (the new version). What is the most efficient way to switch traffic from the 'blue' backend set to the 'green' backend set using the ALB's traffic management capabilities?

• A. Use the ALB's routing rules to gradually shift traffic from the 'blue' backend set to the 'green' backend set based on a percentage weight.
• B. Update the listener to point directly to the 'green' backend set.
• C. Create a new listener that points to the 'green' backend set and delete the old listener.
• D. Update the health check policy of the 'blue' backend set to mark all servers as unhealthy, forcing the ALB to send traffic to the 'green' backend set.

You are designing a multi-tier application within an OCI Virtual Cloud Network (VCN). The application comprises a public-facing web tier in one subnet, an application tier in another, and a database tier in a third.
For security reasons, you want to ensure that only the application tier can initiate connections to the database tier. The web tier needs to be able to communicate with the application tier, but not directly with the database tier. You are using private IP addresses within your VCN. Which procedural step is MOST effective to achieve this network isolation?

• A. Create separate Network Security Groups (NSGs) for each tier and configure ingress and egress rules to restrict traffic accordingly. Configure the route table for the Web Tier subnet to route traffic destined for the Database Tier subnet through the Application Tier.
• B. Create separate security lists for each subnet and configure ingress and egress rules to restrict traffic accordingly. Configure the route table for the Web Tier subnet to route traffic destined for the Database Tier subnet through the Application Tier.
• C. Create separate security lists for each subnet and configure ingress and egress rules to restrict traffic accordingly. Create appropriate route rules in each subnet's route table.
• D. Create a single Network Security Group (NSG) and associate it with all three subnets. Configure ingress and egress rules within the single NSG to restrict traffic accordingly.

Your company is deploying a high-throughput, low-latency financial application on OCI. This application relies on raw TCP connections and requires connection persistence to maintain session state. You anticipate extremely high traffic volume and need a load balancer that can handle millions of concurrent connections with minimal overhead. You also want to use private endpoints. Which OCI load balancing option provides the most appropriate solution to meet these stringent performance and security requirements?

• A. Network Load Balancer with TCP load balancing and 5-Tuple Hash Persistence
• B. Global Load Balancer with TCP load balancing and Cookie-based Persistence
• C. Regional Load Balancer with HTTP load balancing and Source IP Hash Persistence
• D. Regional Load Balancer with TCP load balancing and IP Hash Persistence