how to extend nbdeployutil period available

hi all,

I have different environment and different Master Server, I have a problem with nbdeployutil on one of this Master. I not able to obtain data older than 30 days. I used this 2 different option:

nbdeployutil --gather --hoursago 2160

nbdeployutil --gather --start "08/16/2015 00:00:00" --end "11/16/2015 00:00:00"

I tried to create "traditional" or "capacity" report but the result it is allways the same, the data contained in the report are allways 30 days old. In the other environment I have not any problem, you know if there is some settings ??

thank you,

regards Stefano