AWS Solutions Architect Associate - Serverless, Data Analytics

You have an e-commerce website and you are preparing for Black Friday which is the biggest sale of the year. You expect that your traffic will increase by 100x. Your website already using an SQS Standard Queue, and you're running a fleet of EC2 instances in an Auto Scaling Group to consume SQS messages. What should you do to prepare your SQS Queue?

• Contact AWS Support to pre-warm your SQS Standard Queue

• Enable Auto Scaling in your SQS queue

• Increase the capacity of the SQS queue

• Do nothing, SQS scales automatically

You have an SQS Queue where each consumer polls 10 messages at a time and finishes processing them in 1 minute. After a while, you noticed that the same SQS messages are received by different consumers resulting in your messages being processed more than once. What should you do to resolve this issue?

• Enable Long Polling

• Add DelaySeconds parameter to the messages when being produced

• Increase Visibility Timeout

• Decrease the Visibility Timeout

Answer explanation

When SQS Long Polling is enabled, Amazon SQS reduces the number of empty responses when there are no messages available to return and eliminating false empty responses (when SQS messages are available but aren't included in a response).

SQS Delay Queues is a period of time during which Amazon SQS keeps new SQS messages invisible to consumers. In SQS Delay Queues, a message is hidden when it is first added to the queue. (default: 0 mins, max.: 15 mins)

SQS Visibility Timeout is a period of time during which Amazon SQS prevents other consumers from receiving and processing the message again. In Visibility Timeout, a message is hidden only after it is consumed from the queue. Increasing the Visibility Timeout gives more time to the consumer to process the message and prevent duplicate reading of the message. (default: 30 sec., min.: 0 sec., max.: 12 hours)

Which SQS Queue type allows your messages to be processed exactly once and in order?

• SQS Standard Queue

• SQS Dead Letter Queue

• SQS Delay Queue

• SQS FIFO Queue

Answer explanation

SQS FIFO (First-In-First-Out) Queues have all the capabilities of the SQS Standard Queue, plus the following two features. First, The order in which messages are sent and received are strictly preserved and a message is delivered once and remains available until a consumer process and deletes it. Second, duplicated messages are not introduced into the queue.

You have 3 different applications and you'd like to send them the same message. All 3 applications are using SQS. What is the best approach would you choose?

• Use SQS Replication Feature

• Use SNS + SQS Fan Out Pattern

• Send messages individually to 3 SQS queues

Answer explanation

This is a common pattern where only one message is sent to the SNS topic and then "fan-out" to multiple SQS queues. This approach has the following features: it's fully decoupled, no data loss, and you have the ability to add more SQS queues (more applications) over time.

You have a Kinesis data stream with 6 shards provisioned. This data stream usually receives 5 MB/s of data and sends out 8 MB/s. Occasionally, your traffic spikes up to 2x and you get a ProvisionedThroughputExceeded exception. What should you do to resolve the issue?

• Add more Shards

• Enable Kinesis Replication

• Use SQS as a buffer to Kinesis

Answer explanation

The capacity limits of a Kinesis data stream are defined by the number of shards within the data stream. The limits can be exceeded by either data throughput or the number of reading data calls. Each shard allows for 1 MB/s incoming data and 2 MB/s outgoing data. You should increase the number of shards within your data stream to provide enough capacity.

You have a website where you want to analyze clickstream data such as the sequence of clicks a user makes, the amount of time a user takes, and where the navigation begins and how it ends. You decided to use Amazon Kinesis, so you have configured the website to send clickstream data to a Kinesis data stream. When you check the data sent to your Kinesis data stream, you find that the users' data is not ordered and the data for individual users is spread across many shards. How would you fix this problem?

• There are too many shards, you should only use 1 shard

• You shouldn't use multiple consumers, only one and it should re-order data

• For each record sent to Kinesis, add a partition key that represents the identity of the user

Answer explanation

Kinesis Data Stream uses the partition key associated with each data record to determine which shard a given data record belongs to. When you use the identity of each user as the partition key, this ensures the data for each user is ordered hence sent to the same shard.

You are running an application that produces a large amount of real-time data that you want to load into S3 and Redshift. Also, this data must be transformed before being delivered to its destination. What is the best architecture you can choose?

• SQS + AWS Lambda

• SNS + HTTP Endpoint

• Kinesis Data Streams + Kinesis Data Firehose

Answer explanation

This is a perfect combo of technology for loading data near real-time data into S3 and Redshift. Kinesis Data Firehose supports custom data transformations using AWS Lambda.

Which of the following is NOT a supported subscriber for AWS SNS?

• Amazon Kinesis Data Streams

• Amazon SQS

• HTTP(S) Endpoint

• AWS Lambda

Answer explanation

Note: Kinesis Data Firehose is now supported, but not Kinesis Data Streams.

Which AWS service helps you when you want to send email notifications to your users?

• Amazon SQS with AWS Lambda

• Amazon SNS

• Amazon Kinesis

You're running many micro-services applications on-premises and they communicate using a message broker that supports the MQTT protocol. You're planning to migrate these applications to AWS without re-engineering each app and modifying the code. Which AWS service allows you to get a managed message broker that supports the MQTT protocol?

• Amazon SQS

• Amazon SNS

• Amazon Kinesis

• Amazon MQ

Answer explanation

Amazon MQ supports industry-standard APIs such as JMS and NMS, and protocols for messaging, including AMQP, STOMP, MQTT, and WebSocket.