Pick up preupgrade utility from the Cluster Edition release location. Run it against
the old servers to update the underlying schema so that their structures
are correct for the new server.
Note: Each new version of Adaptive Server contains different features
that introduce new parameters, commands, reserved words, and so
on. For this reason, use
preupgrade to prepare
the old server for an upgrade. However, if you are upgrading from 15.0.1 Cluster Edition or 15.0.3 Cluster Edition to the 15.5 Cluster Edition, you can skip this step.
Note: You see advisory warnings when configuration parameters
are not set to the default. These do not require any action.