Simulation of the CMS detector for the high luminosity upgrade

The efforts around the simulation of the High Luminosity Upgrade of the CMS detector are described in this proceeding. The general strategy aims to provide to the scientific community a tool which allows one to simulate new setups of the CMS detector. The suggested tool is built around a fully parametric Fast Simulation and a simplified Full Simulation setup. The Forward Electromagnetic Calorimeter was used as a benchmark example and is described in details. The propagation of the same approach to the forward hadronic calorimeters and other detectors is briefly discussed.