RDS + Aurora + ElastiCache Flashcards
1
Q
What happens during an RDS Multi-AZ failover and how long does the process take?
A
When the primary RDS instance fails for any reason (Ex: an AZ being down), the AWS RDS service will modify the value of the CNAME record which points to the primary instance and redirects it to the domain name of the secondary instance in the separate AZ, which is promoted as the new primary instance.
Note that it may be necessary to reset the DNS record cache of any connecting applications so that they may request the updated CNAME record.
Failover times are typically between 60-120 seconds.
