05 - Read Replicas for DB

Question 1

Read Replicas

Answer 1

• Read replica are separate things that provide read access only
• Read replicas are asynchronously replicated.
• Small lag in replication
• Can be created in the same region or other regions. Cross region read replica

Question 2

Benefits

Answer 2

• Read replica performance improvement
• max 5 read replicas
• Each read replica provide an addition performance

Question 3

Primary vs. Read Replicas

Answer 3

• Only use the primary for writes
• Can config read replica of read replica but lag a problem
• Global performance improvement - cross region read replicas.
• Snapshots and backups improve RPO
• Read replica offers near 0 RPO
• Can promote a read replica to primary - done in minutes. Low RTO
• Data corruptions can not use the above to recover