During summer 2006 a fraction of the CMS silicon strip tracker was operated in a comprehensive slice test called the Magnet Test and Cosmic Challenge (MT CC). At the MTCC, cosmic rays detected in the muon chambers were used to trigger the readout o f all CMS subdetectors in the general data acquisition system and in the presence of the 4 T magnetic field produced by the CMS superconducting solenoid. This document describ the operation of the Tracker hardware and software prior, during and after data taking. T he performance of the detector as resulting from the MTCC data analysis is also presented.
