amazon web services - Does AWS RDS Multi AZ in conjuction with read replicas have less replication lag than just read replicas? -


quoting aws docs:

"you can use multi-az deployments , read replicas in conjunction enjoy complementary benefits of each. can specify given multi-az deployment source db instance read replicas."

does multi-az read replica have less replication lag ordinary read replicas? ask because multi-az states: "it synchronously replicates data".

also:

"multi-az deployments utilize synchronous replication, making database writes concurrently on both primary , standby standby up-to-date in event failover occurs. while our technological implementation multi-az db instances maximizes data durability in failure scenarios, precludes standby being accessed directly or used read operations. fault tolerance offered multi-az deployments make them natural fit production environments; learn more multi-az deployments, please visit faq section."

multi-az rds establishes secondary replica of db in different az , replicated synchronously. can accessed when promoted being master db instance , used exclusively disaster recovery.

read replicas asynchronous replication of master db instance , can created in 1 or more azs/regions.

the 2 features operate independently of each other. secondary rds instances not used source rr's therefore rr lag constant regardless of rds availability configuration.


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