Exam AWS Certified Solutions Architect - Associate SAA-C03 topic 1 question 601 discussion

The key reasons are: Aurora read replicas allow setting up replication from RDS PostgreSQL to Aurora PostgreSQL with minimal downtime. Once replication is set up, the read replica can be promoted to a full standalone Aurora DB cluster with little to no downtime. This approach leverages AWS's managed replication between the source RDS PostgreSQL instance and Aurora. It avoids having to manually create backups and restore data. Using DB snapshots or pg_dump backups requires manually restoring data which increases downtime and operational overhead. Data import from S3 would require exporting, uploading and then importing data which adds overhead.

B is correct as the question says least down time and data loss

"Use an RDS for PostgreSQL DB instance as the basis for a new Aurora PostgreSQL DB cluster by using an Aurora read replica. The Aurora read replica is available for migrating only within the same AWS Region and account. The Aurora read replica option minimizes downtime during a migration. You can promote the new cluster when you have zero (0) replication lag between the primary RDS instance and the Aurora read replica." https://repost.aws/knowledge-center/aurora-postgresql-migrate-from-rds

Not A: Would work but have some (though minor) downtime B: "The Aurora read replica option minimizes downtime during a migration" Not C: "If your data is stored using Amazon Simple Storage Service (Amazon S3)" ... in this case it is not Not D: "If ... you don't have downtime considerations, you can use this option" https://repost.aws/knowledge-center/aurora-postgresql-migrate-from-rds

ACD will have delta changes issue. Which means, RDS snapshot/export at 2pm, upload/import the table into Aurora, configure and populated completed by 6pm. This created a 4-hour gap of delta changes

please focus, we have RDS not Aurora, I don't know how you vote to create an Aurora read replica to migrate an RDS to Aurora.

LEAST operational overhead = read replica

A,B,C are all valid option. But B: The Aurora read replica option minimizes downtime during a migration.

B is correct guys. Lets see what we got here: C and D is not correct of course. We have to consider A and B. A: migration using a snapshot: this would, of course, introduce heavy data loss and down time B: migration using read replica: nearly no dataloss and downtime.

RDS PostgreSQL to Aurora PostgreSQL: • Option 1: DB Snapshots from RDS PostgreSQL restored as PostgreSQL Aurora DB • Option 2: Create an Aurora Read Replica from your RDS PostgreSQL, and when the replication lag is 0, promote it as its own DB cluster (can take time and cost $)

https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Migrating.html

Answer [B] There are five options for migrating data from your existing Amazon RDS for PostgreSQL database to an Amazon Aurora PostgreSQL-Compatible DB cluster. 1-Using a snapshot 2-Using an Aurora read replica 3-Using a pg_dump utility 4-Using logical replication 5-Using a data import from Amazon S3 (2-Using an Aurora read replica) The Aurora read replica option minimizes downtime during a migration. Which is what the question demand so answer B; is the correct ; https://repost.aws/knowledge-center/aurora-postgresql-migrate-from-rds

https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Migrating.html