[ovs-discuss] Flow table entry in openvswitch

[Jesse Gross]

On Thu, Aug 22, 2013 at 12:02 AM, Gal Sagie <gal.sagie at gmail.com> wrote:
> Hello everyone,
>
> I am new to OpenVswitch and would like to ask a fundamental question
> regarding the flow table.
> I looked the code and saw it has a 12-13 tuple matching key (unless i miss
> understood) which consist of MAC's src and dst IP's , TCP/UDP ports, TOS,
> VLAN...
>
> What i am wondering is why is it not just L2 MAC's ? (with maybe support for
> tunneling)
> Are these flow entries used for openvswitch support of "distirubition
> accross multipile physical networks"  and live migration?
> (VM's on the same hypervisor cant have the same MAC's right? )

Open vSwitch (and OpenFlow) is not just an L2 switch. Since it's
possible to write policies against the upper layers, OVS needs to be
able to match on them.