Known as "Cheese," the coach is working with defensive coordinator/linebackers coach Ellis Johnson, cornerbacks coach Melvin Smith and defensive line coach Rodney Garner to repair what was a broken Auburn defense in 2012.
He notes that Johnson, who gave him his start in the coaching business at Gardner-Webb College, is like a father figure and that Smith, who he has coached with in the past, is like a brother.
Harbison jokes that the other member of the defensive staff, line coach Rodney Garner, is the group's sergeant at arms and has fit in nicely to form a smoothly operating unit.
Commenting on his safeties, Harbison says, "We have a way to go and we are not there yet, but I think we are on track as long as we stay focused, play as unit, do the little things right, become great tacklers and play with great effort and dedication."
Harbison, who moved from Clemson to Auburn, is shown at Auburn's spring football game.
"To me Jermaine had an outstanding spring and he carried it over from the summer to now," Harbison says. "I respect him a great deal. I like the way he carries himself and he is about the team."
"When you get a guy like Holsey, you have got you a good athlete and a good defensive back," Harbison says. "Josh, being able to play the boundary corner and the boundary safety positions, gives us flexibility."
Returning starter Demetrius McNeal has not been able to practice due to a health issue, but is expected to be on the field soon.
"Demetrius has come back focused," Harbison says of the senior. "He is on board. We have Fish (Trent Fisher) and Ryan Smith locked in and we have the young guys, Khari (Khari Harding) and King (Brandon King) coming along."
Smith, who is a senior, and Fisher, who is a junior, give the Tigers two more safeties with starting experience making five in the group if you count Holsey's starts last season as a freshman cornerback.
King, a junior college transfer, had his first practice with the team last week as did Harding, a freshman safety from Oklahoma.
After practicing twice on Friday the players took the day off from workouts on Friday. In addition to their scrimmage on Saturday, they will have another practice that evening.