1Z0-1104-25 Question 77
Select 2Your company has deployed a critical e-commerce application in Oracle Cloud Infrastructure (OCI) and wants to ensure high availability across multiple Availability Domains (ADs). You are asked to configure a public load balancer to minimize downtime and maintain secure connections to the backend servers. Which two configurations should you implement to achieve this goal?
- A
- Provision the public load balancer in two subnets, each in a different AD, and enable TLS termination at the load balancer.
- B
- Configure the load balancer to listen on a single subnet in the primary Availability Domain only to reduce complexity.
- C
- Use health checks on each backend server pool and ensure you have backend servers in at least two ADs.
- D
- Disable routing across Availability Domains to prevent cross-AD traffic.
- E
- Place all backend servers in the same Availability Domain to simplify security group management.
Show answer and explanation
Correct answers: A, C
Explanation
To achieve high availability with an OCI public load balancer, you should provision it in multiple subnets spread across different Availability Domains. This design prevents a single AD failure from impacting the application. In addition, configuring health checks ensures only healthy backend servers receive requests. Reference: Oracle Cloud Infrastructure Load Balancer Documentation, which recommends active-active multi-AD deployments and health-checked backend sets for maximum fault tolerance.
- A. Correct.
Option 1: CORRECT. Placing your public load balancer in two subnets (one in each AD) ensures that if one AD becomes unavailable, the load balancer in the other AD can still serve traffic. Enabling TLS termination at the load balancer also maintains secure connections while offloading encryption processing from the backend.
- B. Incorrect.
Option 2: INCORRECT. Restricting the load balancer to a single AD unnecessarily limits availability. If that AD fails, the service will become inaccessible. High availability requires subnets in multiple ADs.
- C. Correct.
Option 3: CORRECT. Health checks are essential to detect and remove unhealthy servers from rotation. Having backend servers in multiple ADs ensures that if one AD goes down or servers fail, the load balancer can redirect traffic to healthy servers in another AD.
- D. Incorrect.
Option 4: INCORRECT. Disabling cross-AD routing undermines high availability. The load balancer should be able to direct traffic across ADs to healthy backends, improving fault tolerance.
- E. Incorrect.
Option 5: INCORRECT. Placing all backend servers in a single AD does not provide redundancy. If that AD experiences issues, all servers might become unavailable, defeating the purpose of high availability.