VNXe supports only one backend port on the storage system. Even though the hardware component (DPE) looks similar between VNXe3300 and the lower end VNX systems, they have different hardware and software code that runs on them. The VNXe software is not designed to use the second SAS backend port that is provided on the hardware.  So the guidance about spreading the drives across multiple backend ports is correct; but it is not applicable for VNXe systems because these systems have only one backend port. All VNX systems have more than one backend port that you can use.
Hi,  I have a question regarding the SAS cabling on the 3100 and 3300s.  There are two SAS ports 0 & 1 on the back of each DPE. I have setup quite a few 3300s and a few came racked by EMC, but they never connected up DAEs to SAS port 1 on the DPE. Why not? There were 4 DAEs on the last 3300 I installed.  I am currently studying the VNX stuff and they recommend utilising both SAS ports on the DPE 5300, as SAS port 0 is connected to the disks in the DPE and recommend spreading the load. Is this recommended for the VNXe stuff?  Why not use both SAS ports on the VNXe 3100 & 3300 DPE?
VNXe SAS Cabling