Due to relational database products and the theory has been relatively mature, so the RDS is not provide the database service, by means of recreating the wheel instead of RDS database services is to build on the popular relational database, the RDS enables database including MySQL, Oracle, SQL Server, and in 2013 Re: Invent just announced support PostgreSQL,
According to different database engines supported by RDS, the RDS each database instance from 5 gb to 3 TB storage capacity and the size of IOPS capacity from 1000 to 30000, in order to help users to focus on application instead of the database above, Amazon RDS offers a variety of convenient user features,
1. The rapidly expanding database instance, the user can according to need of rapid change such as via the admin console type, parameters such as the size of the database storage,
2. More usable area (Multi - AZ) deployment: the user can choose the RDS database deployment area available on way, such data can synchronously from the main to the standby database, database replication (note: deployment support area available on Oracle, MySQL and PostgreSQL)
3. Automatic data backup: RDS services will automatically backup every day in the backup window time user database, and users can also manually by means of snapshots database backup,
4. Read the copy (Read up) : MySQL based RDS also supports user for each DB instance to create up to 5 Read copy, also can be on the basis of the primary reading copy to create more secondary Read copy,
After introducing the basic knowledge of RDS, we start to talk about today's topic, namely the RDS cross-regional read copy, this is a our new feature launch RDS in last November, as the name implies, RDS cross-regional read copy means now RDS create copies are no longer confined to one region, but can be read copy of cross-regional Settings, so that users can put a copy of RDS database in the area of data by reading in an asynchronous manner for cross-regional transmission,
Cross-regional read copy the main application scenario
RDS across regions to read copy feature is also a feature of user demand is bigger, you can now through this feature for cross-regional disaster is designed, the extended deployment of globalization or the existing database migration to a new area,
1. Improve disaster preparedness design
Although the available area (AZ) provides a good high availability features, but for some deployed on disaster preparedness plan in different area needs of users, they can by reading and cross-regional way in other areas to provide a copy of the database read copy, so that when the primary area of service is not available, users can read the copy through ascension into the primary database to ensure business continuity,
2. The extended deployment of globalization
If your application service user distribution all over the world, so you can read through cross-regional copy to offer your customers more recent database query service, for example, the primary database in the eastern region, the Irish and the Tokyo area each have one copy, read write such applications (green line) by the United States east of the primary database is complete, the application of the read operation (black line) can go to the finish, this way of schematic diagram is as follows:
3. The application of regional migration
Cross-regional copy allows users to read in the application of regional migration has become more simple, AWS before already supported by AMI copy and EBS snapshot copy EC2 instances of cross-regional migration, now read through cross-regional copy can be relatively easy to the realization of the data layer of cross-regional migration, users need only through cross-regional read copy the data migration to new area, first and then read this copy ascension into the main database, the final finish can be applied to the new master database,
Cross-regional read copy create
Cross-regional read copy to create a very simple, the user through the AWS management console RDS management interface to complete the operation, the new reading copy creation wizard interface on a new target area (Destination Region) selection drop-down box, you just need to choose your target area, other read copy parameter is set the same as the original,
All transmission of data between regions is through the way of public key encryption, to ensure data transmission security, the cost of using cross-regional read copy services includes database instance, the relevant storage costs and the cost of data across regions,
Source: the AWS Chinese blog