As IT organizations to move to a converged infrastructure and service-oriented model, many are finding that current data center networking architectures are a limiting factor. VLAN-based switching models have a long history, but suffer from the following challenges in the data center:
* Inflexibility: VLAN and switching boundaries are not flexible nor easily extensible. As requirements grow or shrink, compute and storage resources need to be allocated without major operational overhead.
* Operationally Inefficient Fault Tolerance: High-availability technologies such as VMware Fault Tolerance work best with “flat” Layer 2 networks, but creating and managing this architecture can be operationally difficult, especially at scale.
* VLAN and IP Address Management Limitations: IP address maintenance and VLAN limits become challenges as the data center scales, particularly when strong isolation is required or in service provider environments.
To solve this challenge, VMware, in partnership with leading networking and silicon vendors including Cisco Systems, has created the VXLAN technology. VXLAN is a method for “floating” virtual domains on top of a common networking and virtualization infrastructure. By leveraging industry-standard Ethernet technology, large numbers of virtual domains can be created above an existing network, with complete isolation from each other and the underlying network.
VXLAN offers the following benefits:
* Flexibility: Datacenter server and storage utilization and flexibility is maximized through the support of “stretched clusters” that cross switching and pod boundaries
* Streamlined Network Operations: VXLAN runs on standard Layer 3 IP networks, eliminating the need to build and manage a large Layer 2 underlying transport layer.
* Investment Protection: VXLAN runs over standard switching hardware, with no need for software upgrades or special code versions on the switches
The video below give a nice, easy to understand, technical overview of VXLAN in just 4 minutes.
Source for the text can be found here.