Hii FratianiD, First of all The interface on which you have enabled Qos so on that interface what operations you are Performing.Qos means :->Classification & Prioritization.Classification of Voice,Video & Data |||| Prioritization of Voice over Video ...

Well sorry but these is just like I am keeping my point of View As u said that Nexus all ports are SFP so you have given one Cisco switch with it and then on that switch you have connected server and on that server you have created various DHCP Pool....