Exam AWS Certified DevOps Engineer - Professional DOP-C02 topic 1 question 80 discussion

Use the AWS::CloudFormation::Init type to include metadata on an Amazon EC2 instance for the cfn-init helper script. If your template calls the cfn-init script, the script looks for resource metadata rooted in the AWS::CloudFormation::Init metadata key. Reference: https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-init.html

It's D

Require CloudFormation init for cfn-init and cfn-hup https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/cfn-hup.html https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-init.html

In this scenario, CloudFormation init metadata is the most suitable approach for ensuring that instances launched by the Auto Scaling group have the latest configuration file.

D is correct: <The instances are created and maintained with AWS CloudFormation> means we will only use ACF to satisfy the requirements of this question. <changes to the configuration file to be reflected on all the instances with a minimal delay when the CloudFormation template is updated> means we nead cfn-init, which is a daemon that check for updates and update the changes A and C: no mention of cfn-init B: no mention of CloudFormation init. we need CloudFormation init because cfn-init is specified in CloudFormation init key.

D. cfn-hup poll for cloudformation metadata. B is wrong because putting the config content in launch template instead of metadata, where cfn-hub is not able to poll.

cfn-init is defined inside AWS::CloudFormation::Init

I vote for B

But what happened to the aspect of using source control?

Google Bart says it is B. By using an EC2 launch template resource, the configuration file will be installed and configured on all instances when they are launched. The cfn-init script will also poll for updates to the configuration, so that all instances will have the latest configuration file as soon as it is updated. In addition, the solution will comply with company policy by storing the configuration file in source control along with the AWS infrastructure configuration files. This will ensure that changes to the configuration file are tracked and managed in a consistent way. Option C: Using an AWS Systems Manager Resource Data Sync resource alone is not enough to ensure that all instances have the latest configuration file. The cfn-init script is needed to install and configure the configuration file on the instance, and the cfn-hup script is needed to poll for updates to the configuration.

Selected B: You can have cfn on Launch Config and Launch Template https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/cfn-hup.html https://stackoverflow.com/questions/54691327/cfn-init-for-cloudformation-launchtemplate

I choos B because the config file must be mantained along teh insfrastructure configuration files in source control

B and D are similar. I will go for B, because D doesn't involve EC2 launch templates

cfn-init and cfn-hup are used to update metadata. https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/cfn-hup.html

option C provides a reliable and scalable solution to manage the configuration file for the application running on the EC2 instances, while also adhering to company policies regarding source control for configuration files.

D Metadata: "AWS::CloudFormation::Init":

By using an EC2 launch template, you can include the configuration file content directly in the template. The cfn-init script can be configured to run when the instance is launched. as CloudFormation init metadata is more suitable for configuring instances during stack creation rather than for dynamically updating configuration files.