The network design for ONTAP select has gone through multiple validations. The configuration in your link shows a two-node cluster using 4 1GbE ports. The hypervisor uses only a single 1GbE port. This is a minimum configuration and for a ROBO cluster. (vSphere Remote Office Branch Office) A ROBO cluster normally has only a few VMs with low utilization that are easily serviced by a 1GbE link. The guide also shows the recommended network is 10GbE network ports. If your needs exceed the 1GbE port, a 2 port PCI/PCIE 10GbE network card is only a few hundred dollars. If you have the VMs that you intend for the installation running you can get an idea of the bandwidth used, please refer to the VMware document link below. The bottom of the page show suggestions for network performance. Please let me know if you have questions or concerns. Thank you.