The SDN approach has brought so much energy in the Datacenter that it changed everything. As a result, virtual switches have become a central element of the modern networking. As one of the early adopters of the mighty Cisco Nexus 1000v, accelerated by the Cisco 1010 appliances and deployed in a UCS-based VMware context, I have appreciated, since the beginning, the competitive advantage of becoming virtual.
In the meantime, on the other side of the Moon, Open vSwitch was growing, evolving and improving up to the point where it became, in my opinion, the best virtual switch implementation ever made. I liked the project so much that I have decided to give my small contribution to the community, by writing a mini-book about the subject. Being a system programmer, other than a sysadmin, my intention is to conjugate both sides of the medal in a single coherent vision about the how and why.
The first chapter, still in rough cut but decent enough to be read, is presented here. It’s all about Linux networking, from the moment a packet hits the NIC up to the moment a virtual switch is able to catch it. Practically, it’s an appetizer of what Open vSwitch is capable of, as we will see in the forthcoming chapters.