A large Atlantic City Casino used HPE NonStop Servers to manage all aspects of the casino’s business, but could never take the application down for any reason due to the 24/7 operational aspects of running a casino. As part of a major upgrade, the casino required developing new applications, and also the restructuring of its databases. The original databases included both flat files and SQL tables, but the new databases only used SQL tables. The casino needed to create and place into operation the new applications without impacting any of its ongoing operations.
Shadowbase Solution: Zero Downtime Migration
- The casino creates the new applications on a separate system and copies the online database to the new system.
- The database is kept in synchronization with the operational database via data replication.
- The new applications are then started and tested thoroughly.
- The casino phases over users to the new system without denying service to any of them.
- The old database is kept in synchronization with the new database for a period of time, so that users can be returned to the old system in the event of a problem with the new applications.
The above was adapted from the book: Breaking the Availability Barrier, Volume III: Active/Active Systems in Practice by Paul J. Holenstein, Dr. Bruce Holenstein, and Dr. Bill Highleyman.