The Sligo Rovers player, in his second loan spell at the Ballybofey club, certainly knows where the net is.
Keating struck in just the 5th minute to give the home side a great start.
But Cabinteely continued to plug away and indeed had one effort cleared off the line in the 15th minute.
Harps closed the half the stronger but failed to convert the pressure into anything of substance.
Keating sealed the points in the 69th minute when Packie Mailey’s cross saw the striker head home form close range.
Olie Horgan will be pleased with four points from a possible six in Harps first two outings.