A key requirement for implementing an active/active system is the synchronization of the databases. Each database copy must always be in a consistent state and must reflect the current state of the application.
The Shadowbase solution accomplishes this task by replicating changes made to each database copy to all other copies in the application network. The Shadowbase technology contains a powerful database replication engine which provides bi-directional replication between the database copies and guarantees that all copies remain in a consistent and correct state.
Coupled with the Shadowbase AutoLoader, a powerful online loading utility, the Shadowbase tool set provides everything necessary to convert an existing application into an active/active architecture.
A concern that must be addressed in active/active database synchronization is that of data collisions. A data collision occurs when two nodes make a change to the same row in the database at substantially the same time. Each will replicate its change to the other database copy, thus overwriting the change made there. As a result, the database copies are different and both are wrong. The Shadowbase software can detect collisions and can automatically resolve them in many cases.
Active/Active Pages:
- Part 1 - What is an Active/Active System?
- Part 2 - Why Does Active/Active Work?
- Part 3 - Shadowbase Database Synchronization
- Part 4 - Eliminate Planned Downtime
- Part 5 - Why Choose Shadowbase Technology?
