A company runs a global web application on Amazon EC2 instances behind an Application Load Balancer. The application stores data in Amazon Aurora. The company needs to create a disaster recovery solution and can tolerate up to 30 minutes of downtime and potential data loss. The solution does not need to handle the load when the primary infrastructure is healthy.
What should a solutions architect do to meet these requirements?
To create a disaster recovery solution that can tolerate up to 30 minutes of downtime and potential data loss, the optimal strategy involves setting up infrastructure that can quickly take over in case the primary system fails. Option A suggests deploying the application with necessary infrastructure elements and using Amazon Route 53 to configure active-passive failover, which suits the requirement of not needing to handle load when the primary infrastructure is healthy. Additionally, creating an Aurora Replica in a second AWS Region would ensure that the data is replicated and available in case of a disaster, adhering to the 30-minute downtime and data loss tolerance.
A is correct. - "The solution does not need to handle the load when the primary infrastructure is healthy." => Should use Route 53 Active-Passive ==> Exclude B, C - D is incorrect because "Create an Aurora second primary instance in the second Region.", we need to create an Aurora Replica enough.
Ref link: https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/dns-failover-types.html
Anything that is not instant recovery is active - passive. In active -passive we have : 1. Aws Backup(least op overhead) - RTO/RPO = hours 2. Pilot Light ( Basic Infra is already deployed, but needs to be fully implemented) -RTO/RPO = 10's of minutes. 3. Warm Standby- (Basic infra + runs small loads ( might need to add auto scaling) -RTO/RPO= minutes 4. ( ACTIVE -ACTIVE ) : Multi AZ option : instant here we can tolerate 30 mins hence B,D are incorrect. AWS backup is in hours, hence D is incorrect . therefore A
A does not create the infrastructure in the DR region though.
If this is the quality of the questions in exam, then we are all screwed! I don't think any options are correct. A proabably the most correct, but a big flaw. "Deploy the application with the required infrastructure elements in place." Deploy to where? Fair enough if you assume another region/AZ, but it's not stated and only Aurora replica is mentioned, not the Web/app servers etc.
I really hope the language is better in the exams. Option A is like "do what it takes it to make the solution work".... well then by default it is right until the second part makes it wrong. smh!
'Can tolerate up to 30 minutes of downtime and potential data loss' rules out any option with 'active-active'. Leaves D and A. D is convoluted. Leaving A.
Not A - does not mention a second region for the infrastructure elements. Also, you cannot really "create an Aurora Replica in a second AWS Region", replicas must be in same region unless using Aurora Global Database (which is not mentioned) Not B - would send half of the traffic to the DR region Not C - this could send traffic to the DR instance even when the primary instance is healthy D - the wording "Aurora second primary instance" is a bit strange, but still a "primary instance" is what we would need in the other region. We would still need to establish replication between the databases (like binlog), or restore a snapshot before failover, but in general this option could meet the 30 minute RTO/RPO requirement.
the question doesnt state Aurora MySQL but you can set up cross-region replicas for Aurora MySQL, but not PostgreSQL. the question only says Amazon Aurora, so its left a bit open as Aurora is either MySql or PostgreSQL. this is without using Global Database. tbh i think this question and answers are well off... it is a dump after all.
I agreed with D as the requirements of 30 min downtime and potential data loss and no load consideration when primary instance is healthy. It makes D more feasible than A. Aurora-Replica is normally used for active-active failovers. Be frugal!
A. involves deploying the application and infrastructure elements in the primary Region. An Aurora Replica is created in a second Region to serve as the standby database. Route 53 is configured with active-passive failover, directing traffic to the primary Region by default. In the event of a disaster, Route 53 can automatically redirect traffic to the standby Region, minimizing downtime. Data loss may occur up to the point of the last replication to the standby Region, which can be within the defined tolerance of 30 minutes. Option B, is not necessary in this case as the solution does not need to handle the load when the primary infrastructure is healthy, and it may involve higher complexity and costs. Option C, may introduce additional complexity and potential data loss, as the standby database might not be up-to-date with the primary database. Option D, may be suitable for backup and recovery scenarios but may not provide the required failover and downtime tolerance specified in the requirements.
I vote D, because option A is not highly available. In option A, you can't configure active-passive failover because you haven't created a backup infrastructure.
It is a cross region DR strategy. You need a read replica and Application in another region to have a realistic DR option. The read replica will take few minutes to to promoted/Active and the application is available. Option D lacks clarity on application and Backups can take time to restore.
confused with A and D but D looks more promising when it says doesn't need to handle the load when primary infrastructure is healthy
I went for D as the wording of A is weird.... D seems most plausible
A For those you are choosing D, I have a question for you. How do you guarantee the provisioning of resources will take less than 30 min through AWS Backup?
By excluding other options you can choose A but this option is incomplete as it doesn't mention deploying/recovering the application in secondary region.
A is perfect - Active-Passive Failover: Use this failover configuration when you want a primary group of resources to be available the majority of the time and you want a secondary group of resources to be on standby in case all of the primary resources become unavailable.
A is perfect
Here's why the other options aren't as suitable: B. Active-active failover: Incur higher costs due to running both infrastructures simultaneously and introduces complexity in managing traffic distribution. C. Restoring from snapshot: Could take longer than 30 minutes to recover, exceeding the company's downtime tolerance. D. AWS Backup: Dependent on backup and restore times, potentially exceeding the 30-minute recovery window.
Depending on the Regions involved and the amount of data to be copied, a cross-Region snapshot copy can take hours to complete and will be a factor to consider for the RPO requirements. You need to take this into account when you estimate the RPO of this DR strategy. If you have strict RTO and RPO requirements, you should consider a different DR strategy, such as Amazon Aurora Global Database . https://aws.amazon.com/blogs/database/cost-effective-disaster-recovery-for-amazon-aurora-databases-using-aws-backup/