It is advised that you watch the Amazon CloudWatch “_____” metric (available via the AWS Management
Console or Amazon Cloud Watch APIs) carefully and recreate the Read Replica should it fall behind due to
replication errors.
A.
Write Lag
B.
Read Replica
C.
Replica Lag
D.
Single Replica
C.
The amount of time a Read Replica DB instance lags behind the source DB instance. Applies to MySQL, MariaDB, and PostgreSQL Read Replicas.
http://docs.aws.amazon.com/AmazonCloudWatch/latest/DeveloperGuide/rds-metricscollected.html
C
Q: Which storage engines are supported for use with Amazon RDS for MySQL Read Replicas?
Amazon RDS for MySQL Read Replicas require a transactional storage engine and are only supported for the InnoDB storage engine. Non-transactional MySQL storage engines such as MyISAM might prevent Read Replicas from working as intended. However, if you still choose to use MyISAM with Read Replicas, we advise you to watch the Amazon CloudWatch “Replica Lag” metric (available via the AWS Management Console or Amazon CloudWatch APIs) carefully and recreate the Read Replica should it fall behind due to replication errors. The same considerations apply to the use of temporary tables and any other non-transactional engines.
https://aws.amazon.com/rds/mysql/faqs/
I agree with the answer. C
answer is C
C
Q: Which storage engines are supported for use with Amazon RDS for MySQL Read Replicas?
Amazon RDS for MySQL Read Replicas require a transactional storage engine and are only supported for the InnoDB storage engine. Non-transactional MySQL storage engines such as MyISAM might prevent Read Replicas from working as intended. However, if you still choose to use MyISAM with Read Replicas, we advise you to watch the Amazon CloudWatch “Replica Lag” metric (available via the AWS Management Console or Amazon CloudWatch APIs) carefully and recreate the Read Replica should it fall behind due to replication errors. The same considerations apply to the use of temporary tables and any other non-transactional engines.
https://aws.amazon.com/rds/mysql/faqs/