VXLAN uses theVXLAN Network Identifier (VNI)to identify and isolate virtual Layer 2 or Layer 3 networks in an overlay environment. The VNI field is24 bits long, which allows a theoretical maximum of2²⁴ (approximately 16 million) VNIs. This is a significant improvement over traditional VLAN technology, which supports only 4094 VLAN IDs, and is one of the main reasons VXLAN is adopted in large-scale campus and data center networks.
It is correct thata tenant can be mapped to one or more VNIs. For example, a tenant may use multiple VNIs to represent different broadcast domains or service segments, such as separate VNIs for different subnets or application tiers. However, the statement becomes incorrect when it claims that VXLAN supports a maximum of12 million tenants.
VXLAN does not directly define a fixed maximum number of tenants. VNIs represent virtual networks, not tenants themselves. The actual number of tenants supported depends on how VNIs are allocated and how the network design maps tenants to VNIs. In theory, the upper limit of VNIs is close to 16 million, not 12 million, and the number of tenants is typically much lower and design-dependent.
Therefore, while the description of VNIs being 24 bits long is correct, the conclusion about supporting a maximum of 12 million tenants is incorrect, making the overall statement false.
