If you used the full-text search feature (CBR) in version 3.5.2, you upgrade by installing and configuring version 5.0.0 of IBM® Legacy Content Search Engine (Autonomy K2). After the upgrade, you recreate index areas, called K2 collections, to replace the version 3.5.2 content search indexes.
As of the 4.0 release of P8 Platform, the full-text search feature was removed as a built-in function of the Content Engine. Instead, the remote IBM Legacy Content Search Engine software is installed and configured through Enterprise Manager to enable full-text searching.
To upgrade IBM Legacy Content Search Engine from version 3.5.2 to 5.0.0, you can install and configure the Autonomy K2 product before or after you upgrade Content Engine. After upgrading IBM Legacy Content Search Engine, you create new index areas, and specify classes and property templates for those classes (if so desired). Then you run a classes index job, which is part of the upgrade of Content Engine.