How to remove out of sync slaves older than x days from server

[dotan spector]

 Hi,
Our puppet bootstraps  temporary clusters that runs for couple of hours and then terminate.
Those clusters leftovers remain on the puppet server who tries to contact them all the time.
How can i remove outofsync  leftovers that older then xdays (by script)?

details:

           installation: foreman-installer-1.15.2

           puppet version: puppet-server-3.8.7

Thanks  in advance