An ERP application is deployed across multiple AZs in a single region. In the event of failure, the Recovery Time
Objective (RTO) must be less than 3 hours, and the Recovery Point Objective (RPO) must be 15 minutes the
customer realizes that data corruption occurred roughly 1.5 hours ago.
What DR strategy could be used to achieve this RTO and RPO in the event of this kind of failure?
A.
Take hourly DB backups to S3, with transaction logs stored in S3 every 5 minutes.
B.
Use synchronous database master-slave replication between two availability zones.
C.
Take hourly DB backups to EC2 Instance store volumes with transaction logs stored In S3 every 5 minutes.
D.
Take 15 minute DB backups stored In Glacier with transaction logs stored in S3 every 5 minutes.
a
answer is a
Glacier takes too long to restore
Replication won’t let you go back in time
Instance store is ephermal
Interestingly the question says, “in this type of failure” which is a data corruption failure. So if we take the question strictly as written, C is a perfectly valid solution. They didn’t ask about instance failures. However, in the real world there are more failure scenarios to consider and you end up with A. It’s really crappy of them if they ask a question like this because for their specific use case, C would be better, but who would do that for an overall backup strategy?
Correct answer is A
instance store is ephemeral, its used only for temporary storage
Are these professional certification qs?
@hello
I was told they were. I will be taking this soon to validate.
Did you take exam?Could we depend on this 400ques for Associate level exam?
yes-ish. some repeats. some are associate.
@hello, it is the professional exam quest. and NOT for associate level !!
Hmmm, these are mostly all Associate level. I have taken the exam before and found these questions in associate solutions architect.
It should be B. Because RPO must be 15minutes so we can’t take hourly backup for that requirement
Agree. Answer is B.
A could not provide RPO is 15 minutes.
The issue with B is that it might as well replicate the data corruption.
A is the right answer.
TNX
thanks so much, your reply helps me a lot
A is the answer because the transaction logs will fill in the gaps between the hourly backups
does anyone have the correct answers?
C is the correct answer as the EC2 Instance storage volumes are transferred faster than S3 check :
http://www.rightscale.com/blog/cloud-industry-insights/network-performance-within-amazon-ec2-and-amazon-s3
This wont provide the fault tolerance we seek. If this Instance goes down, data will be gone forever. A is correct
A
A
A. Take hourly DB backups to S3, with transaction logs stored in S3 every 5 minutes.
What if there was a failure after 45 minutes at which time the next backup has not been done? How can you recover the data used 15 mins ago? Remember RPO is 15mins. So I’ll go with B
With master slave replication you will also replicate corrupt data. This only helps with hardware failures.
I think that A correct