1Z0-1072-25 Question 15
Select 3Your organization plans to deploy a web application that experiences unpredictable traffic spikes. You need to keep costs low by running only enough Compute capacity to handle the current load and automatically add or remove instances when usage changes. Which three actions are required to set up an autoscaling instance pool for your application in Oracle Cloud Infrastructure?
- A
Create an instance configuration specifying the shape, image, and network details required by your application.
- B
Launch a single Compute instance in each Availability Domain and configure an alarm to monitor its CPU usage.
- C
Attach an autoscaling configuration to your instance pool with scaling rules based on performance metrics.
- D
Develop a custom image for the OS of each instance in the instance pool before creating an instance configuration.
- E
Create an instance pool using your instance configuration and specify the initial size and placement details.
- F
Attach a public Load Balancer directly to a single instance when traffic spikes, then detach it when usage decreases.
Show answer and explanation
Correct answers: A, C, E
Explanation
To configure an autoscaling environment in OCI, you first create an instance configuration with the desired shape, image, and networking information. Next, you create an instance pool using that configuration and specify the initial size and placement (subnet or Availability Domain). Finally, you attach an autoscaling configuration to the instance pool to automatically increase or decrease the number of instances based on defined performance metrics or schedules. Refer to the Oracle Cloud Infrastructure documentation on 'Instance Configurations' and 'Instance Pools' for detailed setup steps and best practices.
- A. Correct.
Correct: Creating an instance configuration is the first step. It acts as a 'template' defining the shape, image, and networking details (e.g., VCN and subnet) for instances in the pool.
- B. Incorrect.
Incorrect: Merely launching isolated instances in each Availability Domain and adding a CPU alarm will not provide automated scaling across multiple instances. Autoscaling requires an instance pool and associated scaling configuration.
- C. Correct.
Correct: You must attach an autoscaling configuration to the instance pool, defining when to scale out (add instances) or scale in (remove instances) based on performance metrics such as CPU utilization.
- D. Incorrect.
Incorrect: While you can use a custom image, it is not mandatory to develop a new one for every instance in the pool. You can opt for an Oracle-provided image or a single custom image if needed. The key is referencing that image in the instance configuration, not recreating it individually for each instance.
- E. Correct.
Correct: Once you have an instance configuration, you create an instance pool based on that configuration. You must specify details like the pool's size and the subnets in which instances should run.
- F. Incorrect.
Incorrect: A Load Balancer in OCI typically attaches to the instance pool as a backend set for distributing traffic across multiple instances. Attaching and detaching it to a single instance does not provide automated scaling for your entire application and defeats the purpose of a pool.