Hi Ruben,
Please check the following link
http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/service/9_1_1/admin/CUCM_BK_CE552AF7_00_cisco-unified-serviceability-administration-91/CUCM_BK_CE552AF7_00_cisco-unified-serviceability-administration-91_chapter_01100.html#CUP0_RF_SC67F734_00
HTH
Manish