Patent ID: 8200634

Claim:
A computer-readable storage medium containing instructions to configure a processor to perform operations comprising: creating a shadow system, the shadow system comprising an upgraded version of a production system comprising an application and data in a database; copying the at least one of the application and the database from the production system to the shadow system, the copying comprising migrating data of the at least one of the application and the database from the production system to the shadow system; providing, during the migrating, production system for continued productive use of the at least one of the application and the database, the continued productive use comprising receiving one or more changes to the data being migrated; recording, during the migrating, the one or more received changes to the data in a persistency container, at the production system; taking the production system out of productive use after completion of the migrating, the taking of the production system out of productive use comprising at least one of locking the production system to prevent further changes and taking the production system offline; replaying, after the production system has been taken out of productive use, the recorded one or more received changes from the persistency container to the shadow system, the replaying comprising executing the recorded one or more received changes in a sequential order of how the one or more received changes were received such that the data migrated to the shadow system from the production system are updated to reflect the one or more received changes; and initiating productive use at the shadow system to replace the production system after the production system is taken out of productive use.