A company delivers applications over the internet. An Amazon Route 53 public hosted zone is the authoritative DNS service for the company and its internet applications, all of which are offered from the same domain name.
A network engineer is working on a new version of one of the applications. All the application's components are hosted in the AWS Cloud. The application has a three-tier design. The front end is delivered through Amazon EC2 instances that are deployed in public subnets with Elastic IP addresses assigned. The backend components are deployed in private subnets from RFC1918.
Components of the application need to be able to access other components of the application within the application's VPC by using the same host names as the host names that are used over the public internet. The network engineer also needs to accommodate future DNS changes, such as the introduction of new host names or the retirement of DNS entries.
Which combination of steps will meet these requirements? (Choose three.)
Correct Answer:BCD
An IoT company sells hardware sensor modules that periodically send out temperature, humidity, pressure, and location data through the MQTT messaging protocol. The hardware sensor modules send this data to the company's on-premises MQTT brokers that run on Linux servers behind a load balancer. The hardware sensor modules have been hardcoded with public IP addresses to reach the brokers.
The company is growing and is acquiring customers across the world. The existing solution can no longer scale and is introducing additional latency because of the company's global presence. As a result, the company decides to migrate its entire infrastructure from on premises to the AWS Cloud. The company needs to migrate without reconfiguring the hardware sensor modules that are already deployed across the world. The solution also must minimize latency.
The company migrates the MQTT brokers to run on Amazon EC2 instances. What should the company do next to meet these requirements?
Correct Answer:B
A company deploys a new web application on Amazon EC2 instances. The application runs in private subnets in three Availability Zones behind an Application Load Balancer (ALB). Security auditors require encryption of all connections. The company uses Amazon Route 53 for DNS and uses AWS Certificate Manager (ACM) to automate SSL/TLS certificate provisioning. SSL/TLS connections are terminated on the ALB.
The company tests the application with a single EC2 instance and does not observe any problems. However, after production deployment, users report that they can log in but that they cannot use the application. Every new web request restarts the login process.
What should a network engineer do to resolve this issue?
Correct Answer:C
A company plans to deploy a two-tier web application to a new VPC in a single AWS Region. The company has configured the VPC with an internet gateway and four subnets. Two of the subnets are public and have default routes that point to the internet gateway. Two of the subnets are private and share a route table that does not have a default route.
The application will run on a set of Amazon EC2 instances that will be deployed behind an external Application Load Balancer. The EC2 instances must not be directly accessible from the internet. The application will use an Amazon S3 bucket in the same Region to store data. The application will invoke S3 GET API operations and S3 PUT API operations from the EC2 instances. A network engineer must design a VPC architecture that minimizes data transfer cost.
Which solution will meet these requirements?
Correct Answer:C
Option C is the optimal solution as it involves deploying the EC2 instances in the private subnets, which provides additional security benefits. Additionally, creating an S3 gateway endpoint in the VPC will enable the EC2 instances to communicate with Amazon S3 directly, without incurring data transfer costs. This is because the S3 gateway endpoint uses Amazon's private network to transfer data between the VPC and S3, which is not charged for data transfer. Furthermore, specifying the route table of the private subnets during endpoint creation will create routes to Amazon S3, which is required for the EC2 instances tocommunicate with S3.
A company is hosting an application on Amazon EC2 instances behind a Network Load Balancer (NLB). A solutions architect added EC2 instances in a second Availability Zone to improve the availability of the application. The solutions architect added the instances to the NLB target group.
The company's operations team notices that traffic is being routed only to the instances in the first Availability Zone.
What is the MOST operationally efficient solution to resolve this issue?
Correct Answer:A
When adding instances in a new Availability Zone to an existing Network Load Balancer (NLB), it is important to ensure that the new Availability Zone is enabled on the NLB. This will allow traffic to be routed to instances in both Availability Zones. This can be done by editing the settings of the NLB and selecting the new Availability Zone from the list of available zones.