Configuring VXLANs

About VXLANs

Traditional network segmentation is provided by Virtual Local Area Networks (VLANs) standardized under the IEEE 802.1Q group. VLANs provide logical segmentation of the network at Layer 2 or broadcast domains. Due to less than optimal use of available network links with VLANs, there are rigid requirements on the placement of devices in the network and the scalability is limited to a maximum of 4096 VLANs. Using VLANs is a limiting factor when building large multi-tenant data centers.

Virtual Extensible LANs (VXLAN) are designed to provide the same Ethernet Layer 2 network services as VLANs but with greater extensibility and flexibility. When compared to VLANs, VXLANs offer the following benefits:

VXLAN is a Layer 2 overlay scheme over a Layer 3 network. It uses MAC Address-in-User Datagram Protocol (MAC-in-UDP) encapsulation to provide a means to extend Layer 2 segments across the data center network. VXLAN is a solution to support a flexible, large-scale multi-tenant environment over a shared common physical infrastructure. The transport protocol over the physical data center network is IP plus UDP.

VXLAN is supported on non-redundant and redundant spine-leaf topology. VXLAN configuration at high level involves 5 major steps in addition to VLAN, trunk, vLAG, and vRouter configuration as needed.