Exam Professional Data Engineer topic 1 question 218 discussion

https://cloud.google.com/sql/docs/mysql/replication#cross-region-read-replicas

The best option here is C. Create two new read replicas from the new primary instance, one in Region3 and one in a new region. Here's the breakdown: Capacity Restoration: Promoting the Region2 replica makes it the new primary. You need to replicate from this new primary to maintain redundancy and capacity. Creating two replicas (Region3, new region) accomplishes this. Geographic Distribution: Distributing replicas across regions ensures availability if another regional event occurs. Speed: Creating new replicas from the promoted primary is likely faster than promoting another existing replica.

Option C

After promoting the read replica in Region2 to be the new primary instance, creating additional read replicas from it can help distribute the read load and maintain or increase the database's total capacity.

Immediate Failover: Promoting the read replica in Region2 quickly restores database operations in a different region, aligning with disaster recovery goals. Capacity Restoration: Creates two new read replicas from the promoted primary instance (formerly the read replica in Region2). This replaces the lost capacity in Region1 and adds a read replica in a new region for further redundancy.