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Fully agree.
Example:
A retail company hosts its web application on an Auto Scaling group of Amazon EC2 instances deployed across multiple Availability Zones. The Auto Scaling group is configured to maintain a minimum EC2 cluster size and automatically replace unhealthy instances. The EC2 instances are behind an Application Load Balancer so that the load can be spread evenly on all instances. The application target group health check is configured with a fixed HTTP page that queries a dummy item on the database. The web application connects to a Multi-AZ Amazon RDS MySQL instance. A recent outage caused a major loss to the company’s revenue. Upon investigation, it was found that the web server metrics are within the normal range but the database CPU usage is very high, causing the EC2 health checks to timeout. Failing the health checks, the Auto Scaling group continuously replaced the unhealthy instances thus causing the downtime.
Which of the following options should the Solution Architect implement to prevent this from happening again and allow the application to handle more traffic in the future? (Select TWO.)
The answer about adding more read-replicas to the DB- is marked as incorrect.
The justification: This may be possible because creating read replicas is recommended to increase the read performance of an RDS cluster. However, this option does not resolve the original intention to reduce the number of repetitive queries hitting the database.
Now show me the intention not to send health.checks to the the DB in the question.
- Adding read-copies to DB is recommended by documentation
- Adding read-copies to DB – distributes the load, and so makes DB capable to read-load by health.check. So I believe the answer shouldnt be “incorrect”
And there are tons of such things. where to discuss those?
