Three Methods to Install the CodeDeploy Agent on EC2 Instances
A company is using AWS CodeDeploy to deploy an application to an Auto Scaling group. The deployment fails because the instances do not have the CodeDeploy agent installed. Which THREE actions are required to resolve this issue?
Quick Answer
The answer is to use AWS Systems Manager Run Command to install the CodeDeploy agent on existing EC2 instances. This is correct because the CodeDeploy agent is a required piece of software that runs on each target instance to pull and execute deployment instructions from the CodeDeploy service; without it, the instance cannot participate in any deployment. On the AWS Certified SysOps Administrator Associate SOA-C02 exam, this scenario tests your understanding that fixing a failed deployment requires addressing the root cause on existing instances, not just updating launch configurations or deployment groups—a common trap is thinking a new launch configuration alone will retroactively fix running instances. The three required actions are installing the agent via user data for new instances, baking it into a custom AMI, or using Run Command for existing instances. Memory tip: “Run, Bake, or Boot” — Run Command for live instances, bake into an AMI, or boot with user data.
⚠ Common exam trap
Many exam-takers confuse deployment configuration settings (like 'OneAtATime') with the fundamental requirement of having the agent installed, or think that changing the instance type will somehow resolve the agent dependency.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Install the CodeDeploy agent on the instances using user data in the launch configuration.
The CodeDeploy agent must be present on every instance that participates in a deployment, so the fix is to ensure it is installed on current and future instances. Option A is correct because adding the agent installation commands to the launch configuration's user data ensures that every new instance launched by the Auto Scaling group automatically installs the CodeDeploy agent at boot. Option B is correct because baking the CodeDeploy agent into a custom AMI and using that AMI in the launch configuration guarantees the agent is already present on all newly launched instances without relying on boot-time scripts. Option C is correct because AWS Systems Manager Run Command can remotely execute the agent installation script on the already-running instances in the Auto Scaling group, fixing the instances that caused the current deployment to fail. Option D is incorrect because changing the deployment configuration to OneAtATime only alters how many instances are updated at a time; it does not install the missing CodeDeploy agent. Option E is incorrect because changing the instance type has no bearing on whether the CodeDeploy agent is installed and will not resolve the failure.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Install the CodeDeploy agent on the instances using user data in the launch configuration.
Why this is correct
User data in the launch configuration runs at each instance boot, so newly launched Auto Scaling instances install the CodeDeploy agent automatically. This satisfies the requirement that instances joining the group have the agent present before CodeDeploy attempts deployment.
- ✓
Create a new AMI that includes the CodeDeploy agent.
Why this is correct
Baking the CodeDeploy agent into a custom AMI guarantees every instance launched from that AMI already has the agent installed, removing the boot-time dependency. This satisfies the requirement that Auto Scaling instances are deployment-ready without manual intervention.
- ✓
Use AWS Systems Manager Run Command to install the agent on existing instances.
Why this is correct
Systems Manager Run Command targets existing running instances and installs the CodeDeploy agent remotely, remediating instances already in the Auto Scaling group. This satisfies the requirement to fix current instances lacking the agent without terminating or replacing them.
- ✗
Change the deployment configuration to 'OneAtATime'.
Why it's wrong here
OneAtATime alters how many instances deploy concurrently, not whether the CodeDeploy agent exists on them. The agent must be installed, the IAM instance profile must grant CodeDeploy permissions, and the launch configuration or template must include the agent installation so new instances register.
- ✗
Update the Auto Scaling group's launch configuration to use a different instance type.
Why it's wrong here
Instance type is unrelated to agent installation; the deployment fails because the agent is absent, not because of compute capacity. Changing instance type would still leave instances unregistered. This action suits resizing for performance or cost, not resolving a missing CodeDeploy agent.
Visual reference
Go deeper
Related to this question
About these practice questions
Courseiva writes every SOA-C02 question from scratch — 1,169 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
Same concept, more angles
1 more way this is tested on SOA-C02
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A company is using AWS CodeDeploy to deploy an application to an EC2 instances in an Auto Scaling group. The deployment fails because the instances are not reporting to CodeDeploy. What is the most likely cause?
easy- A.The security group does not allow inbound traffic from CodeDeploy.
- B.The instances do not have the correct IAM role to allow CodeDeploy to access them.
- C.The application is not running on the instances.
- ✓ D.The CodeDeploy agent is not installed on the instances.
Why D: The most likely cause is that the CodeDeploy agent is not installed on the instances. The agent is required to communicate with the CodeDeploy service and execute deployments. Option A is incorrect because the security group needs to allow outbound traffic from the instances to CodeDeploy, not inbound. Option B is incorrect because the IAM role is necessary for the instances to access CodeDeploy, but the immediate issue of not reporting is the agent. Option C is incorrect because the application not running is a symptom, not the cause of the reporting failure.
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This SOA-C02 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the SOA-C02 exam.