AWS Aurora

AWS Aurora is a high-performance highly available database engine for AWS.

 

Proprietary AWS tech, not open source

 

supports Postgres and MySQL db

 

is AWS cloud optimized and claims 5x performance improvement over MySQL on RDS

 

and 3x improvement on Postgres on RDS

 

Storage grows automatically in blocks of 10GB to 128TB

 

can have up to 15 replicas vs 5 mysql replicas

 

replication also much faster and failover is almost instantaneous,
failover very fast within 30 secs, and it is HA high availability native

 

self-healing with peer-to-peer replication

 

and supports cross-region replication

 

stores 6 copies of your data across 3 AZs

 

4 copies of 6 needed for writes
3 out of 6 needed for reads

 

provides a writer endpoint that points to the master db.

you can have asg auto-scaling on top (but max 15 replicas)

 

 

patching, updating etc is done by AWS

 

also provides BackTrack service – you can restore a point in time without any extra backup routine

 

important for the exam!

 

READER ENDPOINT connects automatically to ALL the read replicas, so this provides for connection level load balancing for the read replicas

 

storage is highly striped across 100s of volumes

 

security similar to RDS

 

encryption at rest using KMS

 

 

automated backups, snapshots and replicas are also encrypted

 

encryption in flight uses SSL

 

you can authenticate using IAM, same as with RDS

 

but you are responsible for protecting your instance with security groups

 

 

also important – for exam!

 

you cannot SSH into Aurora

 

 

 

 

Aurora Read Replica Auto Scaling

 

You create a writer endpoint for DB writes, while reads go to a single separate reader endpoint, which connects to multiple aurora DBs.

 

As auto scaling takes place and more read DBs are added, these are connected to the reader endpoint

 

However, you can also create a separate custom endpoint for specific other traffic purposes, eg a read analytics software which needs to connect and which generates intensive traffic load

 

or you might want to have a set of read replicas which have different instance type to the others, again, you can use custom endpoints for this, this creates an additional endpoint.

 

Aurora Serverless

 

automated db instance and auto-scaling

 

no need for capacity planning

 

use case:

 

infrequent, unpredictable workloads

 

billing is pay per second, can be more cost-effective

 

client talks to a proxy-fleet and in the backend Aurora creates the necessary instances.

 

 

Important for EXAM!

Aurora Multi-Master

 

every node is Read-Write

 

useful for immediate failover for the WRITE node – offers high availability for the writer node.

 

Global Aurora

 

you can have

 

Cross Region Read Replicas

 

useful for Disaster Recovery (DR)

 

easy to set up

 

Global Database (recommended)

 

you have one primary region for read-write

 

and up to 5 secondary read only regions with v low replication lag
plus up to 16 read replicas per secondary region

 

provides for very low latency

 

when you promote another region for DR the RTO recovery time overhead is less than 1 minute.

 

Aurora Machine Learning

 

you can add ML predictions to apps via sql

supports

 

AWS
– sagemaker
– comprehend – for sentiment analysis

 

can be used for fraud detection, ad targeting, sentiment analysis, product recommendations