For VxRail clusters that can tolerate a single point of failure, and do not have demanding workload requirements, the VxRail cluster can be configured using only the Ethernet ports on the NDC/OCP. Starting with version 7.0.130, for workloads that require a higher level of failure protection, VxRail supports spreading the networks across NDC/OCP Ethernet ports and Ethernet ports on PCIe adapter cards.
The custom network option provides flexibility with the selection of the Ethernet ports to support the VxRail cluster networking. The cluster can be deployed using either the default network profiles supported in VxRail, or you can select the Ethernet ports to be used by the cluster and assign those ports to the VxRail networks. There is more flexibility with the customized port selection option, since you can use just the ports on the NDC/OCP, mix the ports from the NDC/OCP and a PCIe adapter card, or select only ports from PCIe adapter cards. For more details, see Appendix F: Physical Network Switch Examples to understand the most common node connectivity options.
If you later decide to change the topology by migrating the VxRail networks onto other uplinks on the VxRail nodes, this activity can be performed after the cluster is built, as long as the VxRail cluster is at version 7.0.010 or later.