DOP-C02 Exam Dumps : AWS Certified DevOps Engineer - Professional

To implement failover for the application to the secondary Region so that HTTP GET requests meet the desired RTO, the DevOps engineer should use the following solution:

Create a new origin on the distribution for the secondary ALB. A CloudFront origin is the source of the content that CloudFront delivers to viewers. By creating a new origin for the secondary ALB, the DevOps engineer can configure CloudFront to route traffic to the secondary Region when the primary Region is unavailable1

Create a new origin group. Set the original ALB as the primary origin. Configure the origin group to fail over for HTTP 5xx status codes. An origin group is a logical grouping of two origins: a primary origin and a secondary origin. By creating an origin group, the DevOps engineer can specify which origin CloudFront should use as a fallback when the primary origin fails. The DevOps engineer can also define which HTTP status codes should trigger a failover from the primary origin to the secondary origin. By setting the original ALB as the primary origin and configuring the origin group to fail over for HTTP 5xx status codes, the DevOps engineer can ensure that CloudFront will switch to the secondary ALB when the primary ALB returns server errors2

Update the default behavior to use the origin group. A behavior is a set of rules that CloudFront applies when it receives requests for specific URLs or file types. The default behavior applies to all requests that do not match any other behaviors. By updating the default behavior to use the origin group, the DevOps engineer can enable failover routing for all requests that are sent to the distribution3

This solution will meet the requirements because it will automate the failover of the application to the secondary Region with zero-second RTO. When CloudFront receives an HTTP GET request, it will first try to route it to the primary ALB in the primary Region. If the primary ALB is healthy and returns a successful response, CloudFront will deliver it to the viewer. If the primary ALB is unhealthy or returns an HTTP 5xx status code, CloudFront will automatically route the request to the secondary ALB in the secondary Region and deliver its response to the viewer.

The other options are not correct because they either do not provide zero-second RTO or do not work as expected. Creating a second CloudFront distribution that has the secondary ALB as the default origin and creating Amazon Route 53 alias records that have a failover policy is not a good option because it will introduce additional latency and complexity to the solution. Route 53 health checks and DNS propagation can take several minutes or longer, which means that viewers might experience delays or errors when accessing the application during a failover event. Creating Amazon Route 53 alias records that have a failover policy and Evaluate Target Health set to Yes for both ALBs and setting the TTL of both records to O is not a valid option because it will not work with CloudFront distributions. Route 53 does not support health checks for alias records that point to CloudFront distributions, so it cannot detect if an ALB behind a distribution is healthy or not. Creating a CloudFront function that detects HTTP 5xx status codes and returns a 307 Temporary Redirect error response to the secondary ALB is not a valid option because it will not provide zero-second RTO. A 307 Temporary Redirect error response tells viewers to retry their requests with a different URL, which means that viewers will have to make an additional request and wait for another response from CloudFront before reaching the secondary ALB.

1: Adding, Editing, and Deleting Origins - Amazon CloudFront

2: Configuring Origin Failover - Amazon CloudFront

3: Creating or Updating a Cache Behavior - Amazon CloudFront

Using the principalTag in the Permission Set inline policy a logged in user belonging to a specific AD group in the IDP can be permitted access to perform operations on certain resources if their group matches the group used in the PrincipleTag. Basically you are narrowing the scope of privileges assigned via Permission policies conditionally based on whether the logged in user belongs to a specific AD Group in IDP. The mapping of the AD group to the request attributes can be done using SSO attributes where we can pass other attributes like the SAML token as well.

The requirement is to deploy a stateless application with multi-Region fault tolerance , ensuring high availability even if an entire AWS Region becomes unavailable. For this design, traffic must be actively served from both Regions, not only during a failure event.

Option C correctly implements an active-active, multi-Region architecture . By deploying the application to both EKS clusters , each Region is capable of serving traffic independently. Using Amazon Route 53 weighted routing , traffic is distributed across both Application Load Balancers, allowing both Regions to handle requests simultaneously. If one Region becomes unhealthy, Route 53 health checks can stop routing traffic to that Region, maintaining availability.

Implementing Kubernetes readiness and liveness probes ensures that traffic is only sent to healthy pods within each cluster. This provides fault tolerance at both the container level (pod health) and the Regional level (Route 53 routing).

Option A uses a failover routing policy, which results in an active-passive design. While fault tolerant, it does not utilize both Regions simultaneously and provides slower recovery during Region failure. Options B and D deploy the application only in the primary Region, which does not meet multi-Region fault tolerance requirements.

Therefore, Option C delivers the most resilient, highly available, and AWS-recommended architecture for a stateless, multi-Region EKS application.