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Chapter 23: Special MaintenanceProduction Refresh StrategiesThere are two ways to refresh a system: Database copy of the production system Client copy of the production clientA database copy is done by copying the entire production database. The “refreshed” system will be a duplicate of the production system.Client-independent changes will also be captured and copied to the target system. The copy can be made using standard backup tapes, so there is no impact on theproduction system.Making a copy also tests your backup and restore process. All revision history of the “refreshed” system is lost, which is usually: Acceptable for the test/QA system Not acceptable for the DEV system because version history is lost. The target database needs to be as large as the PRD database. After the copy, the target system must be reconfigured. The target system loses its client structure and become a duplicate of the client structureof the PRD system.If the PRD system has one client and the QAS system has three clients, after the databasecopy, the QAS system will have one client. The other two clients are lost.A client copy is done by performing a client copy of the active client from the PRD system(instead of copying the entire database, like a database copy). Unlike a database copy, the target system does not have to be reconfigured. The target system does not lose its client configuration. A client copy requires that the source and target systems are not in use during the copy.Having both systems out of use may not be a practical action for many companiesbecause the amount of time required to do the copy could be significantly greater thanthe amount of time that the production system can be “down.” If there are any client-independent objects (programs, table structures, etc.) that havebeen changed and are not the same in the two systems, these objects will not be copied(refer to the sections on Client Copy below).System Administration Made Easy23–57