Amazon Web Services DOP-C02 Exam With Confidence Using Practice Dumps

 The correct solution is to create a new assertion safety rule in Route 53 ARC and apply it to the two routing controls. An assertion safety rule is a type of safety rule that ensures that a minimum number of routing controls are always enabled. The ATLEAST type of assertion safety rule specifies the minimum number of routing controls that must be enabled for the rule to evaluate as healthy. By setting the threshold to 1, the rule ensures that at least one routing control is always turned on. This prevents the scenario where both routing controls are accidentally turned off and the application becomes unavailable in both Regions.

The other solutions are incorrect because they do not use safety rules to prevent both routing controls from being turned off. A gating safety rule is a type of safety rule that prevents routing control state changes that violate the rule logic. The OR type of gating safety rule specifies that one or more routing controls must be enabled for the rule to evaluate as healthy. However, this rule does not prevent a user from turning off both routing controls manually. A resource set is a collection of resources that are tested for readiness by Route 53 ARC. A readiness check is a test that verifies that all the resources in a resource set are operational. However, these concepts are not related to routing control states or safety rules. Therefore, creating a new resource set and a new readiness check will not ensure that at least one routing control is turned on at all times. References:

Routing control in Amazon Route 53 Application Recovery Controller

Viewing and updating routing control states in Route 53 ARC

Creating a control panel in Route 53 ARC

Creating safety rules in Route 53 ARC

AWS Control Tower provides an integrated governance framework that combines both preventive controls, implemented as Service Control Policies at the OU level, and detective controls, implemented as AWS Config rules applied across all enrolled accounts. Control Tower automatically applies these guardrails to all accounts in enrolled OUs. When new accounts are provisioned through Account Factory, they are automatically enrolled in the assigned OU and receive all applicable preventive and detective controls immediately without manual intervention. Option A uses only SCPs, covering only preventive controls without built-in detective capabilities. Option C requires manually updating stack sets when new accounts are created and does not provide preventive controls via SCPs. Option D provides only detective controls through Config rules with no preventive guardrails. Control Tower is the only option that natively handles both control types and automatically governs newly created accounts.

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This solution will meet the requirements because it will use a rolling restart to gradually replace the EC2 instances in the green environment with new instances that have the new software version installed. A rolling restart is a process that terminates and launches instances in batches, ensuring that there is always a minimum number of healthy instances in service. This way, the green environment can be updated without affecting the availability or performance of the application. When the rolling restart is complete, the DevOps engineer can use an AWS CLI command to modify the listener rules of the ALB and change the default action to forward traffic to the green environment’s target group. This will switch the traffic from the blue environment to the green environment all at once, as required by the question.