RDS P2

read replica

feature ?

Connect using new DNS address

RDS support 5 read replica for RDS and Aurora can up to 15

Can promote to Master, but will break the replication link between primary and secondary

Managed RDS

:

DB update on Master, replicate async and not sync

defintion?

Used to scale out your heavily read RDS

can be in diff region

Can access even your Master DB is down

How AWS create?

by create snapshot

With Multi-AZ off, will cause I/O suspension around 1minute

With MZ on, will not experience performance hit

Optimization ?

Make sure your app can work with RDS

Ex" offload reporting if you use your DB as reporting

scale horizotally: read replica

horizontally scaling technique (= scale out)

  1. Read replicas allow you to create read-only copies.

when user write to master DB, Master DB asynchornos replicate to read replica

user can access read replica to perform read ONLY operation

Currently, RDS read replicas support transparent load balancing of queries or connections.

. RDS MySQL, PostgreSQL, and MariaDB can have up to 5 read replicas, and Amazon Aurora can have up to 15 read replicas.

5.Can place in a different AWS Region closer to your users for better performance.

  1. do automatic failover capabilities that Multi-AZ provides
  1. Can promoting a read replica to a master for faster recovery in the event of a disaster. .

can create nested read replica

but will create latency for this operation

Only up to 4 layers (M-R-R-R)

  1. used case

to reduce the load of Master DB

to aggregate read throughput performance

  1. Asynchronous replicate

Means got time gap

May or may not in sync all the time

replicate ALL database in the source

can 't replicate partial

Support Multi-AZ

can support cross region, cross AZ replication

DB version upgrade can be independent of primary

No backup config by default

click to edit

when primary node is under maintenance, read replica still can be access

Using AWS RDS Multi-AZ & Read Replicas - AWS Training

Each replica has a unique Domain Name Service (DNS) endpoint so that an application can implement load balancing by connecting to the replica endpoint. Let’s look at the options on how we can make applications aware of RDS read replicas.

event notification

**Amazon RDS groups events into categories that you can subscribe to so that you can be notified when an event in that category occurs. Yo

u can subscribe to an event category for a DB instance, DB snapshot, DB security group, or DB parameter group.

Amazon RDS events are published via Amazon SNS and sent to you as an email or text message**

encryption

click to edit

Manage keys used for encrypted DB instances using the AWS KMS. KMS encryption keys are

specific to the region that they are created in.

○ RDS encryption is currently available for all database engines and storage types. RDS encryption

is available for most DB instance classes.

○ You can't have an encrypted Read Replica of an unencrypted DB instance or an unencrypted

Read Replica of an encrypted DB instance.

○ You can't restore an unencrypted backup or snapshot to an encrypted DB instance.

○ You can use SSL from your application to encrypt a connection to a DB instance running MySQL,

MariaDB, SQL Server, Oracle, or PostgreSQL

click to edit