Finalists Ulster will take on Northhampton Saints, Toulon and Montpelier in Pool Four while Connacht once again have been drawn with Conor O'Shea's Harlequins, Biarritz and Italian newcomers Zebre in Pool Three.
Pool One: Munster, Edinburgh, Saracens, Racing Metro.
Pool Two: Toulouse, Leicester, Ospreys, Treviso.
Pool Three: Biarritz, Harlequins, Connacht, Zebre.
Pool Four: Northampton Saints, Ulster, Glasgow, Castres.
Pool Five: Leinster, Clermont Auvergne, Scarlets, Exeter Chiefs.
Pool Six: Cardiff Blues, Toulon, Sale Sharks, Montpelier.