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include static content. They may also contain client-side scripts. Because your storage on Amazon S3 is
virtually unlimited you can scale infinitely. You also do not need to service dynamic content so a database
is not needed.
Reduced Redundancy Storage (RRS) is an Amazon S3 storage option that enables customers to reduce
their costs by storing noncritical, reproducible data at lower levels of redundancy than Amazon S3’s
standard storage.
The two answers are correct as using RRS doesn't alter the solution to the problem in any way. Reference:
http://docs.aws.amazon.com/AmazonS3/latest/dev/WebsiteHosting.html
QUESTION 40
You have designed an application which does the following.
. It checks for new items in an S3 bucket once per hour.
. If new items exist, a message is added to an SQS queue.
. It has several EC2 instances which retrieve messages from the SQS queue, parse the file, and send you
an email containing the relevant information from the file.
You upload a test file to the bucket, wait a couple hours and find that you have hundreds of emails from the
application.
Which of the following is the most likely cause for this volume of email? (Choose 2 answers)
A. To keep multiple instances from processing the same SQS message, your application must delete the
SQS message after processing it.
B. Messages are not being deleted following processing.
C. You are being spammed
D. Your SQS queue is not large enough
Correct Answer: AB
Section: (none)
Explanation
Explanation/Reference:
Explanation: Many instances can poll a single queue, but to keep multiple instances from processing the
same SQS message, your application must delete the SQS message after processing it. While SQS does
not guarantee a message will be processed only once, the same message being processed many times is
probably an indication that the message is not being
deleted following processing Reference:
http://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-how-i t-
works.html#sqs-basic-requirements
QUESTION 41
You are leading the design of your company's AWS cloud environment. Your requirements make it clear
that a few departments will require a low latency network and up to 10GB of performance. You decide that
Placement Groups would be a good option for these departments. What requirements for EC2 instances
should be met when deployed in Placement Groups? (Choose 2 answers)
A. EC2 instances must be in multi-AZ for fault tolerance.
B. EC2 instances must be reserved instances.
C. EC2 instances must be in a single Availability Zone.
D. Choose instance types that support enhanced networking .
Correct Answer: CD
Section: (none)
Explanation
Explanation/Reference:
Explanation: A placement group is a logical grouping of instances within a single Availability Zone.
Placement groups are recommended for applications that benefit from low network latency, high network
throughput, or both. To provide the lowest latency, and the highest packet-
per-second network performance for your placement group, choose an instance type that supports
enhanced networking.
Reference: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/placement-groups.html