The network layer consists of:
The physical connections between the ports on the network switches and the NICs on the VxRail nodes enable communications for the virtual infrastructure within the VxRail cluster. The virtual infrastructure within the VxRail cluster uses the virtual distributed switch to enable communication within the cluster, and communication to IT management and the application user community.
VxRail predefined logical networks manage and control traffic within the cluster and outside of the cluster. Certain VxRail logical networks must be made accessible to the outside community. For instance, IT management requires connectivity to the VxRail management system, and end users and application owners require access to their VMs running in the VxRail cluster. The network traffic supporting I/O to the vSAN datastore or the vMotion network used to dynamically migrate VMs between VxRail nodes to balance workload can stay within the VxRail cluster; otherwise, they can be configured with a routable network. The internal network used for device discovery is isolated and does not exit the ToR switches.
Virtual LANs (VLANs) define the VxRail logical networks within the cluster. They also define the method that is used to control the paths a logical network can pass through. A VLAN, represented as a numeric ID, is assigned to a VxRail logical network. The same VLAN ID is also configured on the individual ports on the ToR switches and on the virtual ports in the virtual distributed switch during the automated implementation process.
When an application or service in the VxRail cluster sends a network packet on the virtual distributed switch, the VLAN ID for the logical network is attached to the packet. The packet can only pass through the ports on the ToR switch and the virtual distributed switch when the VLAN IDs match. We highly recommend isolating the VxRail logical network traffic by using separate VLANs. We recommend using a “flat” network only for test or nonproduction purposes.
The following figure shows the network layer of the VxRail cluster:
Figure 13. Network layer
The VxRail system groups the logical networks in the following categories: External Management, Internal Management, vSAN, vSphere vMotion, and Virtual Machine. The system assigns the settings that you specify for each of these logical networks during the initialization process.
Before VxRail version 4.7, both external and internal management traffic shared the external management network. Starting with VxRail 4.7, the external and internal management networks are separate networks.