Your System Uses a Multi-Master, Multi-Region DynamoDB Configuration Spanning Two

question 15

Multiple Choice

Your system uses a multi-master, multi-region DynamoDB configuration spanning two regions to achieve high availablity. For the first time since launching your system, one of the AWS Regions in which you operate over went down for 3 hours, and the failover worked correctly. However, after recovery, your users are experiencing strange bugs, in which users on different sides of the globe see different data. What is a likely design issue that was not accounted for when launching?

• A) The system does not have Lambda Functor Repair Automatons, to perform table scans and chack for corrupted partition blocks inside the Table in the recovered Region.
• B) The system did not implement DynamoDB Table Defragmentation for restoring partition performance in the Region that experienced an outage, so data is served stale.
• C) The system did not include repair logic and request replay buffering logic for post-failure, to resynchronize data to the Region that was unavailable for a number of hours.
• D) The system did not use DynamoDB Consistent Read requests, so the requests in different areas are not utilizing consensus across Regions at runtime.

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Definitions:

Amphibians

Amphibians are a class of cold-blooded vertebrates that include frogs, toads, salamanders, and newts, characterized by their ability to live both on land and in water.

Chordate Group

A large group of animals that, at some stage in their development, possess a notochord, dorsal nerve cord, pharyngeal slits, and a post-anal tail.

Bony Fishes

Fish that have skeletons primarily composed of bone tissue, as opposed to cartilaginous fishes; this group includes the vast majority of current fish species.

Placoderms

A group of extinct jawed fishes.