Recycle Bin is a data recovery feature that enables you to restore accidentally deleted Amazon EBS snapshots and EBS-backed AMIs. When using Recycle Bin, if your resources are deleted, they are retained in the Recycle Bin for a time period that you specify before being permanently deleted. You can restore a resource from the Recycle Bin at any timebefore its retention period expires. This solution has the least operational overhead, as you do not need to create, copy, or upload any additional resources. You can also manage tags and permissions for AMIs in the Recycle Bin. AMIs in the Recycle Bin do not incur any additional charges. References:

Recover AMIs from the Recycle Bin

Recover an accidentally deleted Linux AMI

In a typical development environment, dev and test databases are mostly utilized for 8 hours a day and sit idle when not in use. However, the databases are billed for the compute and storage costs during this idle time. To reduce the overall cost, Amazon RDS allows instances to be stopped temporarily. While the instance is stopped, you’re charged for storage and backups, but not for the DB instance hours. Please note that a stopped instance will automatically be started after 7 days. This post presents a solution using AWS Lambda and Amazon EventBridge that allows you to schedule a Lambda function to stop and start the idle databases with specific tags to save on compute costs. The second post presents a solution that accomplishes stop and start of the idle Amazon RDS databases using AWS Systems Manager.

https://aws.amazon.com/blogs/database/dynamodb-streams-use-cases-and-design-patterns/

https://aws.amazon.com/premiumsupport/knowledge-center/back-up-dynamodb-s3/

To meet the requirements of the web application in the most secure manner, the company should create a Route 53 Resolver outbound endpoint, create a resolver rule, and associate the resolver rule with the VPC. This solution will allow the application to use private DNS records to communicate with the on-premises services from a VPC. Route 53 Resolver is a service that enables DNS resolution between on-premises networks and AWS VPCs. An outbound endpoint is a set of IP addresses that Resolver uses to forward DNS queries from a VPC to resolvers on an on-premises network. A resolver rule is a rule that specifies the domain names for which Resolver forwards DNS queries to the IP addresses that you specify in the rule. By creating an outbound endpoint and a resolver rule, and associating them with the VPC, the company can securely resolve DNS queries for the on-premises services using private DNS records12.

The other options are not correct because they do not meet the requirements or are not secure. Creating a Route 53 Resolver inbound endpoint, creating a resolver rule, and associating the resolver rule with the VPC is not correct because this solution will allow DNS queries from on-premises networks to access resources in a VPC, not vice versa. An inbound endpoint is a set of IP addresses that Resolver uses to receive DNS queries from resolvers on an on-premises network1. Creating a Route 53 private hosted zone and associating it with the VPC is not correct because this solution will only allow DNS resolution for resources within the VPC or other VPCs that are associated with the same hosted zone. A private hosted zone is a container for DNS records that are only accessible from one or more VPCs3. Creating a Route 53 public hosted zone and creating a record for each service to allow service communication is not correct because this solution will expose the on-premises services to the public internet, which is not secure. A public hosted zone is a container for DNS records that are accessible from anywhere on the internet3.

Send the outbound connection from EC2 to Network Firewall. In Network Firewall, create stateful outbound rules to allow certain domains for software patch download and deny all otherdomains.https://docs.aws.amazon.com/network-firewall/latest/developerguide/suricata-examples.html#suricata-example-domain-filtering

https://aws.amazon.com/blogs/networking-and-content-delivery/deliver-your-apps-dynamic-content-using-amazon-cloudfront-getting-started-template/

RDS supported Storage > https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_Storage.html GP2 max IOPS >https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/general-purpose.html#gp2-performance

Amazon RDS provides three storage types: General Purpose SSD (also known as gp2 and gp3), Provisioned IOPS SSD (also known as io1), and magnetic (also known as standard).They differ in performance characteristics and price, which means that you can tailor your storage performance and cost to the needs of your database workload. You can create MySQL,MariaDB, Oracle, and PostgreSQL RDS DB instances with up to 64 tebibytes (TiB) of storage. You can create SQL Server RDS DB instances with up to 16 TiB of storage. For this amount of storage, use the Provisioned IOPS SSD and General Purpose SSD storage types.https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_Storage.html

 To use an event-driven programming model with AWS Lambda and reduce operational overhead, Amazon API Gateway and Amazon DynamoDB are suitable solutions. Amazon API Gateway can receive the data from the sensors and invoke AWS Lambda functions to process the data. AWS Lambda can run code without provisioning or managing servers, and scale automatically with the incoming requests. Amazon DynamoDB can store the data in a fast and flexible NoSQL database that can handle any amount of data with consistent performance.

This answer is correct because it provides redundancy for the VPN connection between the Management VPC and the data center. If one customer gateway device or one VPN tunnel becomes unavailable, the traffic can still flow over the second customer gateway device and the second VPN tunnel. This way, the single point of failure in the VPN connection is mitigated.

AWS Snowball is a petabyte-scale data transport service that uses secure devices to transfer large amounts of data into and out of the AWS Cloud. Snowball addresses common challenges with large-scale data transfers including high network costs, long transfer times, and security concerns. AWS Snowball can transfer up to 80 TB of data per device, and multiple devices can be used in parallel to meet the migration deadline. AWS Snowball is more cost-effective than AWS Snowmobile, which is designed for exabyte-scale data transfers, or Amazon S3 Transfer Acceleration, which is optimized for fast transfers over long distances. Amazon S3 VPC endpoint does not increase the upload speed, but only provides a secure and private connection between the VPC and S3. References: AWS Snowball, AWS Snowmobile, Amazon S3 Transfer Acceleration, Amazon S3 VPC endpoint

AWS WAF is a web application firewall that helps protect web applications from common web exploits that could affect application availability, compromise security, or consume excessive resources. AWS WAF allows users to create rules that block, allow, or count web requests based on customizable web security rules. One of the types of rules that can be created is an SQL injection rule, which allows users to specify a list of IP addresses or IP address ranges that they want to allow or block. By using AWS WAF to protect the application, the company can prevent SQL injection and other web-based attacks from reaching the application and the database.

RDS parameter groups are collections of parameters that define how a database instance operates. Users can modify the parameters in a parameter group to change the behavior and performance of the database. By using RDS parameter groups to configure the security settings, the company can enforce best practices such as disabling remote root login, requiring SSL connections, and limiting the maximum number of connections.

The other options are not correct because they do not effectively protect the application and the database from SQL injection and other web-based attacks. Using security groups and network ACLs to secure the database and application servers is not sufficient because they only filter traffic at the network layer, not at the application layer. Using AWS Network Firewall to protect the application and the database is not necessary because it is a stateful firewall service that provides network protection for VPCs, not for individual applications or databases. Using different database accounts in the application code for different functions is a good practice, but it does not prevent SQL injection attacks from exploiting vulnerabilities in the application code.

To maintain predictable database performance and ensure that the Lambda invocations do not overload the database with too many connections, a solutions architect should point the client driver at an RDS proxy endpoint and deploy the Lambda functions inside a VPC. An RDS proxy is a fully managed database proxy that allows applications to share connections to a database, improving database availability and scalability. By using an RDS proxy, the Lambda functions can reuse existing connections, rather than creating new ones for every invocation, reducing the connection overhead and latency. Deploying the Lambda functions inside a VPC allows them to access the private RDS DB instance securely and efficiently, without exposing it to the public internet. References:

Using Amazon RDS Proxy with AWS Lambda

Configuring a Lambda function to access resources in a VPC

Cloudfront for rapid response and s3 to minimize infrastructure.

This solution meets the requirements with the least operational overhead because it leverages the features of IAM Identity Center and AWS Control Tower to centrally manage multiple user permissions across all the accounts. By creating new groups and permission sets, the company can assign fine-grained permissions to the developer and administrator teams based on their roles and responsibilities. The permission sets are applied to the groups at the organization level, so they are automatically inherited by all the accounts in the organization. When new users are hired, the company only needs to add them to the appropriate group in IAM Identity Center, and they will automatically get the permissions assigned to that group. This simplifies the user management and reduces the manual effort of assigning permissions to each user individually.

AWS Glue DataBrew is a visual data preparation tool that allows you to easily clean, normalize, and transform your data without writing any code. You can create and run data preparation jobs on your data stored in Amazon S3, Amazon Redshift, or other data sources. AWS Step Functions is a service that lets you coordinate multiple AWS services into serverless workflows. You can use Step Functions to orchestrate your DataBrew jobs, define the order and parallelism of execution, handle errors and retries, and monitor the state of your workflow. By using AWS Glue DataBrew and AWS Step Functions, you can meet the requirements of the company with minimal operational overhead, as you do not need to write any code, manage any servers, or deal with complex dependencies.

This solution meets the requirements because it allows the company to use both predictive scaling and dynamic scaling to optimize the capacity of its Auto Scaling group. Predictive scaling uses machine learning to analyze historical data and forecast future traffic patterns. It then adjusts the desired capacity of the group in advance of the predicted changes. Dynamic scaling uses target tracking to maintain a specified metric (such as CPU utilization) at a target value. It scales the group in or out as needed to keep the metric close to the target. By using both scaling methods, the company can benefitfrom faster, simpler, and more accurate scaling that responds to both forecasted and live changes in utilization.