A. I've experienced a lot of problems with Realtek NICs and Hyper-V, and I've found other people have also hit problems. There seems to be an incompatibility between Realtek and Hyper-V in many situations, in particular jumbo frames, which just won't work. The best solution is to stay away from the Realtek NICs for servers (they're desktop NICs after all). I've had a lot of success using Intel NICs instead. During my research, I heard of similar problems with Broadcom NICs, but I haven't seen this first hand.
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