how to clear the data of haloe before 30 day's automatic

[nifi]

i use cacti086j + plugins + syslog-ng + haloe to get some syslog info from my network devices(more than 100).There is many info everyday,but i just need recently 30 day's data,so how should i do to delete the data a month ago?can i do it automatic???

[Kernelde]

Under "console->settings->Misc" you can set the "Syslog Retention"

[nifi]

thanks！！！