The Cisco UCS M81KR supports virtulization automation using the Cisco VN-Link technology. The Cisco UCS M81KR implements VN-Link technology in hardware (also known as pass through swithcing), with each virtual machine connecting to a virtual interface to execute network policies and switching functions on application-specific integrated circuit (ASIC)-based fabric interconnects. Each VM interface is connected in a Pass-Through way to a unique dynamic Vnic. Each Vnic (Fixed and Dynamic) is connected to the UCS 6100 on a unique VNTag and results in a unique Veth. Each Vnic can be uniquely controlled for VLAN membership, rate limiting and QOS scheduling. Each Dynamic Vnic is late-bound using a Port profile associated to each VM interface. Each VM interface is now a Veth on the UCS 6100. Cisco UCS M81KR also supports VN-Link in software, which is a software-based method of handling traffic to and from a virtual machine and uses the Nexus 1000v virtual switch.
Cisco VN-Link technology provides network visibility to virtual machines, enables configurations and policies to follow the virtual machine during virtual machine migration, and provides consistent network operations model for physical and virtual servers. VN-Link is like creation of a logical link between a vNIC on a virtual machine and a Cisco UCS fabric interconnect. Network policies, called port profiles, can be defined by a network administrator in Cisco UCS Manager and then applied to virtual machines by a server or virtualization administrator in VMware vCenter. As virtual NICs (vNICs) on given virtual machines are added, moved, or deleted, the port group is controlled through VMware vCenter. These port groups are not configured on each VMware ESX Server, but defined as port profiles within the Cisco Unified Computing System.