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)
- 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.
- do automatic failover capabilities that Multi-AZ provides
- 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)
- used case
to reduce the load of Master DB
to aggregate read throughput performance
- 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