RDS And Multi-AZ Failover

Question 1

What is RDS Multi-AZ?

Answer 1

Creates a copy of the RDS DB in another AZ. AWS manages the failure from one AZ to another automatically.

Question 2

How does RDS Multi-AZ work?

Answer 2

RDS DB is provided with a DNS that points to one AZ. if the AZ fails, AWS will update the DNS to point to another AZ.

Question 3

When AWS RDS implements failover and changes the DNS to point to another AZ, what steps does that customer take?

Answer 3

None. Since the DNS changes automatically, as long as the customer points their application to the DNS, the transition is automatic.

Question 4

What steps must the customer take to ensure the standby RDS instance is in sync with the primary?

Answer 4

None. AWS manages the replication.

Question 5

During an RDS failover event, how long can a customer expect their application to be unresponsive?

Answer 5

About 1 minute.

Question 6

for synchronizing MySQL, Oracle, and PostgreSQL, what does AWS utilize?

Answer 6

synchronous physical replication

Question 7

for synchronizing MSSQL what does AWS utilize?

Answer 7

synchronous logical replication, employing SQL Server-native mirroring technology

Question 8

True or False, backups and restores are taken from the primary DB?

Answer 8

False. They are both taken from the secondary to avoid I/O interference on the primary.

Question 9

How can you test failover functionality?

Answer 9

By forcing a reboot of the primary DB instance.

Question 10

What two ways can you reboot a DB instance?

Answer 10

AWS Management console

RebootDBInstance API call

Question 11

would RDS Multi-AZ be used for scaling and increasing performance?

Answer 11

No. Use read replicas for scaling and performance.