IBM manual Introduction to DB2 deployment

1.3.1New environment versus environment with existing DB2 installation

Unless given deployment is to take place in a brand new environment, it is likely that DB2 client product or servers are already in place. As such, you should take full inventory of all the DB2 clients and server currently in place as well as the users and applications that utilize them. If the DB2 product is currently installed in an environment where deployment is to take place, consider the compatibility of the various DB2 versions. Note that connections to and from DB2 V7 to V9.5 are not supported.

Another consideration is installing multiple products and versions in the same system. As of Version 9 and later, you can install and run multiple DB2 copies on the same computer, where a DB2 copy refers to one or more installation of DB2 database products in a particular location on the same computer. Each of the DB2 Version 9.x copies can be at the same or different code levels.

This means that:

￿Applications that require different DB2 versions on the same computer at the same time can be deployed.

￿Independent copies of DB2 products for different functions can be run on the same system.

￿Testing is allowed on the same computer before moving the production database to the later version of the DB2 product.

￿Independent Software Vendors (ISPs) can embed a DB2 server product into their product and hide the DB2 database from end users.

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