Examkin

Soru

Zorluk: OrtaRoute 53 Routing Policies and DNS Failover Strategies

A company hosts its main portal at the apex domain `example.com`. The application runs on Amazon EC2 instances behind an Application Load Balancer (ALB) in the `us-east-1` Region. The company wants to implement an active-passive disaster recovery strategy. If the ALB or the primary application becomes unhealthy, users must be redirected to a static maintenance page hosted on an Amazon S3 bucket configured for website hosting in the `us-west-2` Region. The database backend requires manual failover, so DNS routing must strictly route all users to the primary ALB under normal operations and only to the S3 bucket during a failure. Which two configurations should the solutions architect implement to meet these requirements?

  1. Create a Route 53 Failover Alias record for `example.com` pointing to the Application Load Balancer in `us-east-1`, set the Failover Record Type to Primary, and set Evaluate Target Health to Yes.Cevap
  2. Create a Route 53 Failover Alias record for `example.com` pointing to the Amazon S3 static website endpoint in `us-west-2`, set the Failover Record Type to Secondary, and set Evaluate Target Health to No.Cevap
  3. C
    Create a Route 53 Latency Alias record for `example.com` pointing to the Application Load Balancer in `us-east-1` and set Evaluate Target Health to Yes to dynamically route users.
  4. D
    Create a CNAME record for `example.com` pointing to the Application Load Balancer DNS name, and configure a Route 53 HTTP health check to monitor the backend instances.
  5. E
    Create a Route 53 Failover record pointing to the Amazon RDS Read Replica, allowing Route 53 to automatically promote the replica to primary if the master database fails.

Cevap

Create a Route 53 Failover Alias record for the apex domain pointing to the Application Load Balancer in the primary region, set the record type as Primary, and enable Evaluate Target Health. Additionally, create a Route 53 Failover Alias record pointing to the S3 static website endpoint, set the record type as Secondary, and disable Evaluate Target Health.
To establish an active-passive failover for an apex domain, the solutions architect must configure Route 53 Failover Alias records. The Primary record points to the Application Load Balancer with Evaluate Target Health set to Yes. This configuration allows Route 53 to evaluate the health of the ALB and failover if the ALB is unhealthy. The Secondary record points to the S3 bucket website endpoint with Evaluate Target Health set to No, since the bucket serves as the static maintenance page and does not require further health validation.

Adım Adım Çözüm

1
Determine the apex domain record requirements
Identify that the zone apex (`example.com`) cannot use a CNAME record, necessitating the use of Route 53 Alias records.
DNS standards prevent mapping a CNAME record directly to the root of a domain.
2
Configure the primary routing policy
Create a Failover Alias record pointing to the primary Application Load Balancer (ALB) and enable Evaluate Target Health.
This allows Route 53 to determine the health of the ALB using its built-in health indicators and dynamically failover when necessary.
3
Configure the backup routing policy
Create a Secondary Failover Alias record pointing to the Amazon S3 static website endpoint and disable Evaluate Target Health.
Disabling Evaluate Target Health on the secondary endpoint ensures traffic is successfully directed to the maintenance page during a failover event, without checking the health of the static page itself.

Anahtar Kavram

Route 53 active-passive DNS failover using Alias records at the zone apex
Bu soruyu puanla

Konular

Route 53 Routing Policies and DNS Failover Strategies

Bu konudan daha fazla soru