Chapter 4. Network considerations

The undercloud host requires at least the following networks:

Provisioning network - Provides DHCP and PXE boot functions to help discover bare-metal systems for use in the overcloud.
External network - A separate network for remote connectivity to all nodes. The interface connecting to this network requires a routable IP address, either defined statically or dynamically through an external DHCP service.

The minimal overcloud network configuration includes the following NIC configurations:

Single NIC configuration - One NIC for the provisioning network on the native VLAN and tagged VLANs that use subnets for the different overcloud network types.
Dual NIC configuration - One NIC for the provisioning network and the other NIC for the external network.
Dual NIC configuration - One NIC for the provisioning network on the native VLAN and the other NIC for tagged VLANs that use subnets for the different overcloud network types.
Multiple NIC configuration - Each NIC uses a subnet for a different overcloud network type.

For more information on the networking requirements, see Networking requirements.