- (Exam Topic 1)
A company is running a serverless application on AWS Lambda The application stores data in an Amazon RDS for MySQL DB instance Usage has steadily increased and recently there have been numerous "too many connections" errors when the Lambda function attempts to connect to the database The company already has configured the database to use the maximum max_connections value that is possible
What should a SysOps administrator do to resolve these errors'?

1. A. Create a read replica of the database Use Amazon Route 53 to create a weighted DNS record that contains both databases
2. B. Use Amazon RDS Proxy to create a proxy Update the connection string in the Lambda function
3. C. Increase the value in the max_connect_errors parameter in the parameter group that the database uses
4. D. Update the Lambda function's reserved concurrency to a higher value

Correct Answer: B
https://aws.amazon.com/blogs/compute/using-amazon-rds-proxy-with-aws-lambda/
RDS Proxy acts as an intermediary between your application and an RDS database. RDS Proxy establishes and manages the necessary connection pools to your database so that your application creates fewer database connections. Your Lambda functions interact with RDS Proxy instead of your database instance. It handles the connection pooling necessary for scaling many simultaneous connections created by concurrent Lambda functions. This allows your Lambda applications to reuse existing connections, rather than creating new connections for every function invocation.
Check "Database proxy for Amazon RDS" section in the link to see how RDS proxy help Lambda handle huge connections to RDS MySQL
https://aws.amazon.com/blogs/compute/using-amazon-rds-proxy-with-aws-lambda/

- (Exam Topic 1)
A SysOps administrator needs to delete an AWS CloudFormation stack that is no longer in use. The CloudFormation stack is in the DELETE_FAILED state. The SysOps administrator has validated the permissions that are required to delete the Cloud Formation stack.

1. A. The configured timeout to delete the stack was too low for the delete operation to complete.
2. B. The stack contains nested stacks that must be manually deleted fast.
3. C. The stack was deployed with the -disable rollback option.
4. D. There are additional resources associated with a security group in the stack
5. E. There are Amazon S3 buckets that still contain objects in the stack.

Correct Answer: DE

- (Exam Topic 1)
A company is using an Amazon DynamoDB table for data. A SysOps administrator must configure replication of the table to another AWS Region for disaster recovery.
What should the SysOps administrator do to meet this requirement?

1. A. Enable DynamoDB Accelerator (DAX).
2. B. Enable DynamoDB Streams, and add a global secondary index (GSI).
3. C. Enable DynamoDB Streams, and-add a global table Region.
4. D. Enable point-in-time recovery.

Correct Answer: C

- (Exam Topic 1)
A company has a VPC with public and private subnets. An Amazon EC2 based application resides in the private subnets and needs to process raw .csv files stored in an Amazon S3 bucket. A SysOps administrator has set up the correct IAM role with the required permissions for the application to access the S3 bucket, but the application is unable to communicate with the S3 bucket.
Which action will solve this problem while adhering to least privilege access?

1. A. Add a bucket policy to the S3 bucket permitting access from the IAM role.
2. B. Attach an S3 gateway endpoint to the VP
3. C. Configure the route table for the private subnet.
4. D. Configure the route table to allow the instances on the private subnet access through the internet gateway.
5. E. Create a NAT gateway in a private subnet and configure the route table for the private subnets.

Correct Answer: B
Technology to use is a VPC endpoint - "A VPC endpoint enables private connections between your VPC and supported AWS services and VPC endpoint services powered by AWS PrivateLink. AWS PrivateLink is a technology that enables you to privately access services by using private IP addresses. Traffic between your VPC and the other service does not leave the Amazon network." S3 is an example of a gateway endpoint. We want to see services in AWS while not leaving the VPC.

- (Exam Topic 1)
A company has an existing web application that runs on two Amazon EC2 instances behind an Application Load Balancer (ALB) across two Availability Zones The application uses an Amazon RDS Multi-AZ DB Instance Amazon Route 53 record sets route requests tor dynamic content to the load balancer and requests for static content to an Amazon S3 bucket Site visitors are reporting extremely long loading times.
Which actions should be taken to improve the performance of the website? (Select TWO )

1. A. Add Amazon CloudFront caching for static content
2. B. Change the load balancer listener from HTTPS to TCP
3. C. Enable Amazon Route 53 latency-based routing
4. D. Implement Amazon EC2 Auto Scaling for the web servers
5. E. Move the static content from Amazon S3 to the web servers

Correct Answer: AD