NSX host overlay network preparation

Two additional virtual NICs are created on each VxRail node to support the host overlay network during the initial deployment of Cloud Foundation on VxRail. This overlay network uses encapsulation to enable the passage of Layer 2 traffic across transport zones in the VI workload domains with a Layer 3 network. Each virtual NIC supporting the overlay network requires a routable IP address.

You can have these IP addresses input into Cloud Builder and assigned to the NICs during Cloud Foundation on VxRail deployment, or leverage DHCP services for IP address assignment. If your requirements include deploying VxRail stretched clusters to support Cloud Foundation, DHCP is the only supported method for IP address assignment.

1. Prepare a pool of IP addresses that is at least equal to double the number of VxRail nodes planned for the deployment.

2. Deploy a DHCP server in the data center, if necessary.
3. Configure the pool of IP addresses for DHCP services to support the NSX host overlay network.
4. Configure the data center network so that NSX host overlay network can reach the DHCP server.

Figure 52.    NSX host overlay uplinks IP addresses assigned by DHCP

Note: If the VLAN cannot be extended out to the DHCP server, enabling ‘DHCP helper’ services on the host overlay VLAN is recommended, if supported on the leaf switches.

Figure 53.    DHCP helper connects DHCP services to host overlay VLAN