LAN SDN technology hard core insider 4 from computing virtualization to network virtualization

Mentioned earlier , With the proliferation of server cores , Virtualization has become a necessary component of the data center . In order to batch manage a large number of virtual machines , There are open source cloud computing platforms ——OpenStack, And based on OpenStack A large number of commercial releases of , Such as H3C CloudOS, Easystack, Kyushu cloud, etc . in fact ,OpenStack It has become the industry standard of Cloud Computing .

stay OpenStack in , There is an important one “ Virtual private cloud ”(VPC) The concept of . Every VPC Contains several subnets , As shown in the figure below ：

At every VPC in , Virtual machines in the same network segment pass vSwitch Interworking , Virtual machines of different network segments pass vRouter route . Out VPC The flow can pass vFW and vLB Realize address translation 、 Load balancing and other functions .

We know , Every virtual machine has its host entity —— Physical servers , that ,OpenStack Where are the host entities of these virtual network elements ？