Oracle RDS GoldenGate support

Oracle GoldenGate can be used with Amazon RDS for Oracle for active-active database replication, zero-downtime migration and upgrades, disaster recovery and data protection, and cross region replication. 

More information here: http://aws.amazon.com/about-aws/whats-new/2014/04/03/you-can-now-use-oracle-goldengate-with-amazon-rds-for-oracle/

EC2 instances in public subnet calling S3 in same region

Traffic to and from S3 and  EC2 (in a public subnet) doesn’t go over the public Internet  in the same region.The traffic goes to the “AWS edge” (Internet Gateway) in that region.  It is the “public Internet” in the sense that you need an Internet Gateway, and S3’s endpoints are Internet-facing. However, the traffic does not move beyond the AWS-controlled networks if you stay within the same region.  The EC2 Instances (or other AWS services)  traffic simply travels via the Internet Gateway to S3. Obviously, for EC2 instance in private subnets they traffic would need to go through a NAT instance.

RDS cross region snapshots

Great news for AWS RDS users looking to provide extra DR protection to their SQL Server, Oracle and MySQL databases: http://aws.amazon.com/about-aws/whats-new/2013/10/31/announcing-point-and-click-copy-of-amazon-rds-db-snapshots-across-aws-regions/

Traffic costs between EC2 instances, AZs, and VPCs

Often times when running on AWS you will have multiple AZs, accounts and VPCs.  This is a simple summary of EC2 data transfer costs:

1. Within the same AZ  : Free: It is within the same AZ and over private IP.
2. Between two AZs :   Cost. Will incur inter-az charges for both inbound and outbound

3. Between Accounts in different VPCs :  Cost. Inter-az charges are applicable for data transfer charges between instances in the different AZ's (same region) and in different accounts.
4. Between one EC2 classic instance and VPC EC2 instance in a same AZ : Cost
5. Instances to S3 in the same region: Free
6. Instance to S3 in different region: Cost. cross region charges

DynamoDB cross region support

DynamoDB does currently not support cross-region replication. Therefore, were you to store your data in two (or more) regions, you would have to roll out your own implementation to replicate.

SNS cross region support

SNS is available in all AWS regions.  It is possible to publish SNS topics and one region and have subscribers in another region.

AWS data transfer costs

Some times instance reside in different AZs and these instances need to share data. Instances also use S3 for things like backups. Here is breakdown of data transfer cost for some typical scenarios: 

1. Instance to Instance in same AZ 
Cost: Free
2. Instance to Instance in different AZ
Cost: Inter-AZ charge for both inbound and outbound
3. Instance to Instance in different account in same or different AZ
Cost: Inter-az charges are applicable for data transfer charges between instances in the different AZ's (same region) and in different accounts
4. Instance to S3 in the same region
Cost: Free

AWS RDS cross region replication

RDS offers a simple way to replicate across AZs (Multi-AZ feature) for fault tolerance and high availability.  RDS cross region synchronization / replication provides additional fault tolerance.  This is an interesting situation because RDS is a 'black box'/PaaS/DaaS environment. Therefore, no access to the OS level is provided. This means this replication solutions like MySQL Replication or Oracle Goldengate can not be used.  Until RDS offers snapshots like the new EBS region snapshotting, you will have to use tools like BitTorrent or CloudBeam to move database dump files across regions.You could use DB links with materialized views as this article mentions: http://aws.amazon.com/articles/4173109646282306. DB Links are slow but if you don't have a low RTO and RPO you could use this...Or come up with your own creative solution.

AWS data movement and replication product

Attunity CloudBeam offers data movement and replication from on premise and AWS, and between AWS regions;
https://aws.amazon.com/marketplace/pp/B00B5PB8IM/ref=srh_res_product_title?ie=UTF8&sr=0-2&qid=1359126283717

AWS EBS cross region migration

AWS offers the capability to migrate an EBS volume from one region to another.  The feature applies to any application or database data:
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-copy-snapshot.html

This can be used to move Oracle database EBS snapshot from one region to another for HA and DR.

AWS Four DR scenarios

There are four DR scenarios that highlight usage of AWS in a DR and a 'HA-lite' situation:

•  Backup and Restore - For systems running on AWS, customers also back up into Amazon S3. Snapshots of Elastic Block Store (EBS) volumes and backups of Amazon RDS are stored in Amazon S3. Alternatively, you can copy files directly into Amazon S3, or you can choose to create backup files and copy them to Amazon S3.
• Pilot Light for Simple Recovery into AWS - This scenario is similar to a Backup and Restore scenario, however, you must ensure that you have the most critical core elements of your system already configured and running in AWS (the pilot light). When the time comes for recovery, you would then rapidly provision a full scale production environment around the critical core. The database data would be replicated to S3. You would typically have some pre-configured servers bundled as Amazon Machine Images (AMIs), which are ready to be started up at a moment’s notice.  These servers could be EC2 instances that have been stopped.
• Warm Standby Solution - A warm standby solution extends the pilot light elements and preparation. It further decreases the recovery time because in this case, some services are always running. By identifying your business-critical systems, you would fully duplicate these systems on in another AWS zone or region and have them always on.  This would insure that the EC2 capacity is available in a disaster.
•  Active-Active Solution - A multi-site solution runs in another AZ or zone in an active-active configuration. The data replication method that you employ will be determined by the recovery point (RPO) you choose.

Cross region AWS Services

There are a few AWS services that are cross region:

• IAM
• Cloud Front
• Route 53