AWS SQS and SNS Quiz

What is the maximum message size supported by AWS SQS?

• 128 KB

• 256 KB

• 512 KB

• 1 MB

Answer explanation

AWS SQS supports a maximum message size of 256 KB. If you need to send larger messages, you can use Amazon S3 to store the data and include a pointer to the S3 object in the SQS message.

Which type of SQS queue guarantees exactly-once processing and strict message ordering?

• Standard Queue

• FIFO Queue

• Dead-letter Queue

• Priority Queue

Answer explanation

FIFO (First-In-First-Out) Queues guarantee that messages are processed exactly once and in the order they are sent. Standard queues provide best-effort ordering and may deliver messages more than once.

What is the default visibility timeout for a message in SQS?

• 10 seconds

• 30 seconds

• 1 minute

• 5 minutes

Answer explanation

The default visibility timeout for a message in SQS is 30 seconds. This is the time during which the message is hidden from other consumers after being retrieved by one consumer. You can adjust this timeout based on your application's needs.

What is the purpose of a dead-letter queue (DLQ) in SQS?

• To store messages that are processed successfully

• To store messages that fail to be processed after a specified number of retries

• To store messages with the highest priority

• To store messages that are delayed

Answer explanation

Correct Answer: b) To store messages that fail to be processed after a specified number of retries
Explanation: A dead-letter queue (DLQ) is used to store messages that cannot be processed successfully after a specified number of retries. This helps in debugging and analyzing failed messages without blocking the main queue.

What is the maximum retention period for messages in an SQS queue?

• 1 day

• 4 days

• 14 days

• 30 days

Answer explanation

Correct Answer: c) 14 days
Explanation: The maximum retention period for messages in an SQS queue is 14 days. The default retention period is 4 days, but you can configure it up to 14 days.

What is the maximum message size supported by AWS SNS for SMS messages?

• 128 KB

• 256 KB

• 512 KB

• 2 MB

Answer explanation

Correct Answer: b) 256 KB
Explanation: The maximum message size for SMS messages in AWS SNS is 256 KB. For other protocols like HTTP/HTTPS or Lambda, the maximum message size is 2 MB.

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

• Email

• SMS

• FTP

• Lambda Function

Answer explanation

Correct Answer: c) FTP
Explanation: AWS SNS supports endpoints like Email, SMS, Lambda Functions, and HTTP/HTTPS, but it does not support FTP as an endpoint type.

What is the primary purpose of an SNS topic?

• To store messages for later processing

• To act as a communication channel for publishers and subscribers

• To encrypt messages using KMS

• To trigger SQS queues

Answer explanation

Explanation: An SNS topic is a communication channel that allows publishers to send messages to multiple subscribers (e.g., email, SMS, Lambda functions). It does not store messages for later processing.

Which AWS service can be used to filter messages in SNS based on attributes?

• SQS

• Lambda

• SNS Message Filtering

• CloudWatch

Answer explanation

Explanation: SNS Message Filtering allows subscribers to receive only the messages that match specific attributes. This reduces unnecessary message delivery to subscribers.

What is the maximum number of subscribers that can be associated with a single SNS topic?

• 10,000

• 100,000

• 1,000,000

• No limit

Answer explanation

Correct Answer: d) No limit
Explanation: There is no limit to the number of subscribers that can be associated with a single SNS topic. You can have millions of subscribers, including email addresses, phone numbers, and other endpoints.