You Need Your API Backed by DynamoDB to Stay Online

question 309

Multiple Choice

You need your API backed by DynamoDB to stay online during a 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 region. Create an Auto Scaling Group behind an ELB in each of the two regions DynamoDB is running in. Add a Route53 Latency DNS Record with DNS Failover, using the ELBs in the two regions as the resource records.
• B) Set up a DynamoDB Multi-Region table. Create an Auto Scaling Group behind an ELB in each of the two regions DynamoDB is running in. Add a Route53 Latency DNS Record with DNS Failover, using the ELBs in the two regions as the resource records.
• C) Set up a DynamoDB Multi-Region table. 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 crossregion ELB.
• D) Set up DynamoDB cross-region replication in a master-standby configuration, with a single standby in another region. 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.

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Definitions:

Plowing Back

The reinvestment of earnings by a company back into its own operation or projects, also known as retained earnings.

ROE

Return on Equity, a financial ratio that measures the profitability of a business in relation to shareholder’s equity, indicating how well a company uses investments to generate earnings growth.

Dividend Growth Rate

The annualized percentage rate of growth of a company's dividend payments.

Constant Growth DDM

A valuation model for stocks that assumes dividends grow at a constant rate in perpetuity, used to calculate the present value of future dividend payments.