WhizQuiz Nov 13th, 2018


#1

There is a requirement for a high availability and disaster recovery plan for an organization. Below are the key points for this plan:
- Once stored successfully, the data should not be lost. This is the key requirement.
- Recovery time can be long as this could save on cost.
Which of the following options would be the best one for this corporation, given the concerns that they have outlined to you above?

  • A. Make sure you have RDS set up as an asynchronous Multi-AZ deployment, which automatically provisions and maintains an asynchronous “standby” replica in a different Availability Zone.
  • B. Set up a number of smaller instances in a different region, which all have Auto Scaling and Elastic Load Balancing enabled. If there is a network outage, then these instances will auto scale up. As long as spot instances are used and the instances are small this should remain a cost effective solution.
  • C. Backup and restoring with S3 should be considered due to the low cost of S3 storage. Backup up frequently and the data can be sent to S3 using either Direct Connect or Storage Gateway or over the Internet.
  • D. Set up pre-configured servers using Amazon Machine Images. Use an Elastic IP and Route 53 to quickly switch over to your new infrastructure if there are any problems when you run your health checks.

0 voters


#2

“The Correct Answer is Option C”

Option A is incorrect because it can help in maintaining data, but is not low on cost and is a high-cost option since you need to maintain a multi-AZ environment. Hence we need to count this option out.

Option B is incorrect because it does not talk about data loss avoidance and is more of network avoidance.

Option C is CORRECT because S3 provides durable, highly available, low cost and more secure storage solution.

Option D is incorrect because it talks about AMI’s but not about the underlying data on EBS storage which will need to be backed up.

More information about Amazon S3:

Amazon S3 is storage for the Internet. It’s a simple storage service that offers software developers a highly-scalable, reliable, and low-latency data storage infrastructure at very low costs

For more information on S3 please refer to the below link:

http://docs.aws.amazon.com/AmazonS3/latest/dev/Welcome.html

So, The correct answer is: Backup and restoring with S3 should be considered due to the low cost of S3 storage. Backup up frequently and the data can be sent to S3 using either Direct Connect or Storage Gateway, or over the Internet."


#3

This is another example of bad question.
It’s not clear where the data is located. If it’s RDS, then Multi-AZ is the only option the guarantees against data loss, because Multi-AZ deployment implements synchronous write. So, in that case cost does not matter, it’s the only solution. On the other hand, answer A somehow talks about asynchronous Multi-AZ, which does not exist (asynchronous read-replica is NOT Multi-AZ deployment, though it’s similar).
S3 backups are good, but they do not prevent data loss, because you do backups at some interval. I assume “no data loss” means RPO=0.
Only synchronous multi-site write prevents data loss. And even in that case, there is a question of region outage.
Again, bad question for the exam. Not to point fingers at WhizLabs, it’s Amazon’s fault.