DOP-C01 Exam - AWS Certified DevOps Engineer- Professional

NEW QUESTION 1
You are currently planning on using Autoscaling to launch instances which have an application installed. Which of the following methods will help ensure the instances are up and running in the shortest span of time to take in traffic from the users?

• A. Loginto each instance and install the software.
• B. UseUserData to launch scripts to install the software.
• C. UseDocker containers to launch the software.
• D. UseAMI's which already have the software installed.

Answer: D

Explanation:
The AM I will be the fatest because it will already have the software installed. You can customize the instance that you launch from a public AMI and then save that configuration as a custom AMI for your own use. Instances that you launch from your AMI use all the custom izations that you've made.
For more information on AMI'S please refer to the below link http://docs.aws.amazon.com/AWSCC2/latest/UserGuide/AMIs.html

NEW QUESTION 2
Which of the following design strategies is ideal when designing loosely coupled systems. Choose 2 answers from the options given below

• A. Having the web and worker roles running on the same set of EC2 Instances
• B. Having the web and worker roles running on separate EC2 Instances
• C. Using SNS to establish communication between the web and worker roles
• D. Using SQS to establish communication between the web and worker roles

Answer: BD

Explanation:
The below diagram shows the ideal design which uses SQS and separate environments for web and worker processes. The SQS queue manages the communication between the web and worker roles.

One example is the way Elastic beanstalk manages worker environments. For more information on
this, please visit the below URL:
◆ http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/using-features-managing-env-tiers.htmI

NEW QUESTION 3
You have written a CloudFormation template that creates 1 elastic load balancer fronting 2 EC2 instances. Which section of the template should you edit so that the DNS of the load balancer is returned upon creation of the stack?

• A. Resources
• B. Parameters
• C. Outputs
• D. Mappings

Answer: C

Explanation:
The below example shows a simple Cloud Formation template. It creates an CC2 instance based on the AMI - ami-d6f32ab5. When the instance is created, it will output the A2 in which it is created.

To understand more on Cloud Formation, please visit the URL:
• https://aws.amazon.com/cloudformation/

NEW QUESTION 4
What would you set in your CloudFormation template to fire up different instance sizes based off of environment type? i.e. (If this is for prod, use m1.large instead of t1.micro)

• A. Outputs
• B. Resources
• C. Mappings
• D. conditions

Answer: D

Explanation:
The optional Conditions section includes statements that define when a resource is created or when a property is defined. For example, you can compare whether a value is equal to another value. Based on the result of that condition, you can conditionally create resources. If you have multiple conditions, separate them with commas.
For more information on Cloudformation conditions please visit the below link
http://docs^ws.a mazon.com/AWSCIoudFormation/latest/UserGuide/cond itions-section- structure.htm I

NEW QUESTION 5
For AWS Auto Scaling, what is the first transition state an instance enters after leaving steady state when scaling in due to health check failure or decreased load?

• A. Terminating
• B. Detaching
• C. Terminating:Wait
• D. EnteringStandby

Answer: A

Explanation:
The below diagram shows the Lifecycle policy. When the scale-in happens, the first action is the Terminating action.

For more information on Autoscaling Lifecycle, please refer to the below link: http://docs.aws.amazon.com/autoscaling/latest/userguide/AutoScaingGroupLifecycle.html

NEW QUESTION 6
You have defined a Linux based instance stack in Opswork. You now want to attach a database to the Opswork stack. Which of the below is an important step to ensure that the application on the Linux instances can communicate with the database

• A. Addanother stack with the database layer and attach it to the application stack.
• B. ConfigureSSL so that the instance can communicate with the database
• C. Addthe appropriate driver packages to ensure the application can work with thedatabase
• D. Configuredatabase tags for the Opswork application layerOpswork application layer

Answer: C

Explanation:
The AWS documentation mentions the below point Important
For Linux stacks, if you want to associate an Amazon RDS service layer with your app, you must add the appropriate driver package to the associated app server layer,
as follows:
1. Click Layers in the navigation pane and open the app server's Recipes tab.
2. Click Edit and add the appropriate driver package to OS Packages. For example, you should specify mysql if the layer contains Amazon Linux instances and mysql-client if the layer contains Ubuntu instances.
3. Save the changes and redeploy the app.
For more information on Opswork app connectivity, please visit the below URL: http://docs.aws.amazon.com/opsworks/latest/userguide/workingapps-connectdb.htmI

NEW QUESTION 7
You are using Jenkins as your continuous integration systems for the application hosted in AWS. The builds are then placed on newly launched EC2 Instances. You want to ensure that the overall cost of the entire continuous integration and deployment pipeline is minimized. Which of the below options would meet these requirements? Choose 2 answers from the options given below

• A. Ensurethat all build tests are conducted using Jenkins before deploying the build tonewly launched EC2 Instances.
• B. Ensurethat all build tests are conducted on the newly launched EC2 Instances.
• C. Ensurethe Instances are launched only when the build tests are completed.
• D. Ensurethe Instances are created beforehand for faster turnaround time for theapplication builds to be placed.

Answer: AC

Explanation:
To ensure low cost, one can carry out the build tests on the Jenkins server itself. Once the build tests are completed, the build can then be transferred onto newly launched CC2 Instances.
For more information on AWS and Jenkins, please visit the below URL:
• https://aws.amazon.com/getting-started/projects/setup-jenkins-build-server/
Option D is incorrect. It would be right choice in case the requirement is to get better speed.

NEW QUESTION 8
You have the following application to be setup in AWS
1) A web tier hosted on EC2 Instances
2) Session data to be written to DynamoDB
3) Log files to be written to Microsoft SQL Server
How can you allow an application to write data to a DynamoDB table?

• A. Add an 1AM user to a running EC2 instance.
• B. Add an 1AM user that allows write access to the DynamoDB table.
• C. Create an 1AM role that allows read access to the DynamoDB table.
• D. Create an 1AM role that allows write access to the DynamoDB table.

Answer: D

Explanation:
I AM roles are designed so that your applications can securely make API requests from your instances, without requiring you to manage the security credentials that
the applications use. Instead of creating and distributing your AWS credentials For more information on 1AM Roles please refer to the below link:
http://docs.aws.amazon.com/AWSCC2/latest/UserGuide/iam-roles-for-amazon-ec2.html

NEW QUESTION 9
Which of the following CLI commands can be used to describe the stack resources.

• A. awscloudformationdescribe-stack
• B. awscloudformationdescribe-stack-resources
• C. awscloudformation list-stack-resources
• D. awscloudformation list-stack

Answer: C

Explanation:
Answer - C
This is given in the AWS Documentation list-stack-resources
Description
Returns descriptions of all resources of the specified stack.
For deleted stacks, ListStackResources returns resource information for up to 90 days after the stack has been deleted.
See also: AWS API Documentation
See 'aws help' for descriptions of global parameters.
list-stack-resources is a paginated operation. Multiple API calls may be issued in order to retrieve the entire data set of results. You can disable pagination by providing the —no-paginate argument. When using —output text and the —query argument on a paginated response, the —query argument must extract data from the results of the following query expressions: StackResourceSummaries For more information on the CLI command, please visit the below URL:
http://docs.aws.amazon.com/cli/latest/reference/cloudformation/list-stack-resources.html

NEW QUESTION 10
Which of the following Cloudformation helper scripts can help install packages on EC2 resources

• A. cfn-init
• B. cfn-signal
• C. cfn-get-metadata
• D. cfn-hup

Answer: A

Explanation:
The AWS Documentation mentions
Currently, AWS CloudFormation provides the following helpers:
cf n-init: Used to retrieve and interpret the resource metadata, installing packages, creating files and starting services.
cf n-signal: A simple wrapper to signal an AWS CloudFormation CreationPolicy or WaitCondition,
enabling you to synchronize other resources in the stack with the application being ready.
cf n-get-metadata: A wrapper script making it easy to retrieve either all metadata defined for a resource or path to a specific key or subtree of the resource metadata.
cf n-hup: A daemon to check for updates to metadata and execute custom hooks when the changes are detected. For more information on helper scripts, please visit the below URL: http://docs.aws.amazon.com/AWSCIoudFormation/latest/UserGuide/cfn-helper-scripts-reference.htmI

NEW QUESTION 11
You have just been assigned to take care of the Automated resources which have been setup by your company in AWS. You are looking at integrating some of the company's chef recipes to be used for the existing Opswork stacks already setup in AWS. But when you go to the recipes section, you cannot see the option to add any recipes. What could be the reason for this?

• A. Onceyou create a stack, you cannot assign custom recipe's, this needs to be donewhen the stack is created.
• B. Onceyou create layers in the stack, you cannot assign custom recipe's, this needsto be done when the layers are created.
• C. Thestack layers were created without the custom cookbooks optio
• D. Just change thelayer settings accordingly.
• E. Thestacks were created without the custom cookbooks optio
• F. Just change the stacksettings accordingly.

Answer: D

Explanation:
The AWS Documentation mentions the below
To have a stack install and use custom cookbooks, you must configure the stack to enable custom cookbooks, if it is not already configured. You must then provide the repository URL and any related information such as a password.
For more information on Custom cookbooks for Opswork, please visit the below URL:
• http://docs.aws.amazon.com/opsworks/latest/userguide/workingcookbook-i nstallingcustom- enable.htm I

NEW QUESTION 12
As part of your continuous deployment process, your application undergoes an I/O load performance test before it is deployed to production using new AMIs. The application uses one Amazon EBS PIOPS volume per instance and requires consistent I/O performance.
Which of the following must be carried out to ensure that I/O load performance tests yield the correct results in a repeatable manner?

• A. Ensurethat the I/O block sizes for the test are randomly selected.
• B. Ensurethat the Amazon EBS volumes have been pre-warmed by reading all the blocksbefore the test.
• C. Ensurethat snapshots of the Amazon EBS volumes are created as a backup.
• D. Ensurethat the Amazon EBS volume is encrypted.

Answer: B

Explanation:
Since the AMI will get all the data from S3 as snapshots, always ensure the volume prewarmed before it is set for the load test.
For more information on benchmarking procedures please see the below link:
• hrtp://docs^ws.amazon.com/AWSCC2/latest/UserGuide/berK;hmark_prooedures.html

NEW QUESTION 13
Which of the following run command types are available for opswork stacks? Choose 3 answers from the options given below.

• A. UpdateCustom Cookbooks
• B. Execute Recipes
• C. Configure
• D. UnDeploy

Answer: ABC

NEW QUESTION 14
Which of the following tools is available to send logdatafrom EC2 Instances.

• A. CloudWatch LogsAgent
• B. CloudWatchAgent
• C. Logsconsole.
• D. LogsStream

Answer: A

Explanation:
The AWS Documentation mentions the following
The CloudWatch Logs agent provides an automated way to send log data to Cloud Watch Logs from Amazon L~C2 instances. The agent is comprised of the following components:
A plug-in to the AWS CLI that pushes log data to CloudWatch Logs.
A script (daemon) that initiates the process to push data to CloudWatch Logs.
Acron job that ensures that the daemon is always running. For more information on Cloudwatch logs Agent, please see the below link:
http://docs.aws.a mazon.com/AmazonCloudWatch/latest/logs/AgentRefe re nee. htm I

NEW QUESTION 15
Your current log analysis application takes more than four hours to generate a report of the top 10 users of your web application. You have been asked to implement a system that can report this information in real time, ensure that the report is always up to date, and handle increases in the number of requests to your web application. Choose the option that is cost-effective and can fulfill the
requirements.

• A. Publishyour data to CloudWatch Logs, and configure your application to autoscale tohandle the load on demand.
• B. Publishyour log data to an Amazon S3 bucke
• C. Use AWS CloudFormation to create an AutoScalinggroup to scale your post-processing application which is configured topull down your log files stored in Amazon S3.
• D. Postyour log data to an Amazon Kinesis data stream, and subscribe yourlog-processing application so that is configured to process your logging data.
• E. Configurean Auto Scalinggroup to increase the size of your Amazon EMR cluster

Answer: C

Explanation:
The AWS Documentation mentions the below
Amazon Kinesis makes it easy to collect, process, and analyze real-time, streaming data so you can get timely insights and react quickly to new information. Amazon
Kinesis offers key capabilities to cost effectively process streaming data at any scale, along with the flexibility to choose the tools that best suit the requirements of
your application. With Amazon Kinesis, you can ingest real-time data such as application logs, website clickstreams, loT telemetry data, and more into your
databases, data lakes and data warehouses, or build your own real-time applications using this data.
Amazon Kinesis enables you to process and analyze data as it
arrives and respond in real-time instead of having to wait until all your data is collected before the processing can begin.
For more information on AWS Kinesis please see the below link:
• https://aws.amazon.com/kinesis/

NEW QUESTION 16
You need your API backed by DynamoDB to stay online duringa total regional AWS failure. You can tolerate a couple minutes of lag or slowness during a large failure event, but the system should recover with normal operation after those few minutes. What is a good approach?

• A. Set up DynamoDB cross-region replication in a master-standby configuration, with a single standby in another regio
• B. Create an Auto Scaling Group behind an ELB in each of the two regions for your application layer in which DynamoDB is running i
• C. Add a Route53 Latency DNS Record with DNS Failover, using the ELBs in the two regions as the resource records.
• D. Set up a DynamoDB Global tabl
• E. Create an Auto Scaling Group behind an ELB in each of the two regions for your application layer in which the DynamoDB is running i
• F. Add a Route53 Latency DNS Record with DNS Failover, using the ELBs in the two regions as the resource records.
• G. Set up a DynamoDB Multi-Region tabl
• H. Create a cross-region ELB pointing to a cross-region Auto Scaling Group, and direct a Route53 Latency DNS Record with DNS Failover to the cross-region ELB.
• I. Set up DynamoDB cross-region replication in a master-standby configuration, with a single standbyin another regio
• J. Create a crossregion ELB pointing to a cross-region Auto Scaling Group, and direct a Route53 Latency DNS Record with DNS Failover to the cross- region ELB.

Answer: B

Explanation:
Updated based on latest AWS updates
Option A is invalid because using Latency based routing will sent traffic on the region with the standby instance. This is an active/passive replication and you can't write to the standby table unless there is a failover. Answer A can wort: only if you use a failover routing policy.
Option D is invalid because there is no concept of a cross region CLB.
Amazon DynamoDBglobal tables provide a fully managed solution for deploying a multi-region, multi-master database, without having to build and maintain your
own replication solution. When you create a global table, you specify the AWS regions where you want the table to be available. DynamoDB performs all of the
necessary tasks to create identical tables in these regions, and propagate ongoing data changes to all of them.
For more information on DynamoDB GlobalTables, please visit the below URL: https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/GlobalTables.html

NEW QUESTION 17
You have an application running a specific process that is critical to the application's functionality, and have added the health check process to your Auto Scaling Group. The instances are showing healthy but the application itself is not working as it should. What could be the issue with the health check, since it is still showing the instances as healthy.

• A. You do not have the time range in the health check properly configured
• B. It is not possible for a health check to monitor a process that involves the application
• C. The health check is not configured properly
• D. The health check is not checking the application process

Answer: D

Explanation:
If you have custom health checks, you can send the information from your health checks to Auto Scaling so that Auto Scaling can use this information. For example, if
you determine that an instance is not functioning as expected, you can set the health status of the instance to Unhealthy. The next time that Auto Scaling performs a
health check on the instance, it will determine that the instance is unhealthy and then launch a replacement instance
For more information on Autoscaling health checks, please refer to the below document link: from AWS
http://docs.aws.amazon.com/autoscaling/latest/userguide/healthcheck.html

NEW QUESTION 18
As part of your deployment process, you are configuring your continuous integration (CI) system to build AMIs. You want to build them in an automated manner that is also cost-efficient. Which method should you use?

• A. Attachan Amazon EBS volume to your CI instance, build the root file system of yourimage on the volume, and use the Createlmage API call to create an AMI out ofthis volume.
• B. Havethe CI system launch a new instance, bootstrap the code and apps onto theinstance and create an AMI out of it.
• C. Uploadall contents of the image to Amazon S3 launch the base instance, download allof the contents from Amazon S3 and create the AMI.
• D. Havethe CI system launch a new spot instance bootstrap the code and apps onto theinstance and create an AMI out of it.

Answer: D

Explanation:
The AWS documentation mentions the following
If your organization uses Jenkins software in a CI/CD pipeline, you can add Automation as a post- build step to pre-install application releases into Amazon Machine Images (AMIs). You can also use the Jenkins scheduling feature to call Automation and create your own operating system (OS) patching cadence
For more information on Automation with Jenkins, please visit the link:
• http://docs.aws.a mazon.com/systems-manager/latest/userguide/automation-jenkinsJntm I
• https://wiki.jenkins.io/display/JCNKINS/Amazon < CC21 Plugin

NEW QUESTION 19
As part of your continuous deployment process, your application undergoes an I/O load performance test before it is deployed to production using new AMIs. The application uses one Amazon Elastic Block Store (EBS) PIOPS volume per instance and requires consistent I/O performance. Which of the following must be carried out to ensure that I/O load performance tests yield the correct results in a repeatable manner?

• A. Ensure that the I/O block sizes for the test are randomly selected.
• B. Ensure that the Amazon EBS volumes have been pre-warmed by reading all the blocks before the test.
• C. Ensure that snapshots of the Amazon EBS volumes are created as a backup.
• D. Ensure that the Amazon EBS volume is encrypted.

Answer: B

Explanation:
During the AMI-creation process, Amazon CC2 creates snapshots of your instance's root volume and any other CBS volumes attached to your instance
New CBS volumes receive their maximum performance the moment that they are available and do not require initialization (formerly known as pre-warming).
However, storage blocks on volumes that were restored from snapshots must to initialized (pulled
down from Amazon S3 and written to the volume) before you can access the block. This preliminary action takes time and can cause a significant increase in the latency of an I/O operation the first time each block is accessed. For most applications, amortizing this cost over the lifetime of the volume is acceptable.
Option A is invalid because block sizes are predetermined and should not be randomly selected. Option C is invalid because this is part of continuous integration and hence volumes can be destroyed after the test and hence there should not be snapshots created unnecessarily
Option D is invalid because the encryption is a security feature and not part of load tests normally. For more information on CBS initialization please refer to the below link:
• http://docs.aws.a mazon.com/AWSCC2/latest/UserGuide/ebs-in itialize.html

NEW QUESTION 20
You have launched a cloudformation template, but are receiving a failure notification after the template was launched. What is the default behavior of Cloudformation in such a case

• A. It will rollback all the resources that were created up to the failure point.
• B. It will keep all the resources that were created up to the failure point.
• C. It will prompt the user on whether to keep or terminate the already created resources
• D. It will continue with the creation of the next resource in the stack

Answer: A

Explanation:
The AWS Documentation mentions
AWS Cloud Formation ensures all stack resources are created or deleted as appropriate. Because AWS CloudFormation treats the stack resources as a single unit,
they must all be created or deleted successfully for the stack to be created or deleted. If a resource cannot be created, AWS CloudFormation rolls the stack back and automatically deletes any resources that were created.
For more information on Cloudformation, please refer to the below link: http://docs.aws.amazon.com/AWSCIoudFormation/latest/UserGuide/stacks.html

NEW QUESTION 21
When thinking of AWS Elastic Beanstalk's model, which is true?

• A. Applications have many deployments, deployments have many environments.
• B. Environments have many applications, applications have many deployments.
• C. Applications have many environments, environments have many deployments.
• D. Deployments have many environments, environments have many applications.

Answer: C

Explanation:
The first step in using Elastic Beanstalk is to create an application, which represents your web application in AWS. In Elastic Beanstalk an application serves as a
container for the environments that run your web app, and versions of your web app's source code, saved configurations, logs and other artifacts that you create
while using Elastic Beanstalk.
For more information on Applications, please refer to the below link: http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/applications.html
Deploying a new version of your application to an environment is typically a fairly quick process. The new source bundle is deployed to an instance and extracted, and the the web container or application server picks up the new version and restarts if necessary. During deployment, your application might still become unavailable to users for a few seconds. You can prevent this by configuring your environment to use rolling deployments to deploy the new version to instances in batches. For more information on deployment, please refer to the below link: http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/using-features.de ploy-existing-version, html

NEW QUESTION 22
Which of the following file needs to be included along with your source code binaries when your application uses the EC2/On-Premises compute platform, and deploy it using the AWS Code Deploy service.

• A. appspec.yml
• B. appconfig.yml
• C. appspecjson
• D. appconfigjson

Answer: A

Explanation:
The AWS Documentation mentions the below
The application specification file (AppSpec file) is a YAML-formatted file used by AWS CodeDeploy to determine:
what it should install onto your instances from your application revision in Amazon S3 or GitHub. which lifecycle event hooks to run in response to deployment lifecycle events. An AppSpec file must be named appspec.yml and it must be placed in the root of an application's source code's directory structure. Otherwise, deployments will fail. For more information on the appspec file, please visit the below URL:
http://docs.aws.amazon.com/codedeploy/latest/userguide/reference-appspec-file.html
Note: If you deploying your code on AWS Lambda compute platform. An AppSpec file can be YAML- formatted or JSON-for matted. You can also enter the contents of an AppSpec file directly into AWS CodeDeploy console when you create a deployment.
However, this question is about along with your source code binaries on an CC2/On-Premises Compute Platform. So, an AppSpec file must be a YAM L-formatted file named appspec.yml and it must be placed in the root of the directory structure of an application's source code. Otherwise, deployments fail.

NEW QUESTION 23
Which of the following is the default deployment mechanism used by Elastic Beanstalk when the application is created via Console or EBCLI?

• A. All at Once
• B. Rolling Deployments
• C. Rolling with additional batch
• D. Immutable

Answer: B

Explanation:
The AWS documentation mentions
AWS Elastic Beanstalk provides several options for how deployments are processed, including deployment policies (All at once. Rolling, Rolling with additional batch,
and Immutable) and options that let you configure batch size and health check behavior during deployments. By default, your environment uses rolling deployments
if you created it with the console or EB CLI, or all at once deployments if you created it with a different client (API, SDK or AWS CLI).
For more information on Elastic Beanstalk deployments, please refer to the below link:
• http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/using-features.rolling-version- deploy.html

NEW QUESTION 24
......