On Tue, Dec 15, 2015 at 11:45:56AM +0300, Pavel Fedin wrote: > To tell the truth, i don't know. I am also learning qemu internals on the > fly. Indeed, i see that it should announce itself. But > this brings up a question: why do we need special announce procedure in > vhost-user then?
I have the same question. Here is my guess... In customized networks, maybe people are not using ARP at all? When we use DPDK, we directly pass through the network logic inside kernel itself. So logically all the network protocols could be customized by the user of it. In the customized network, maybe there is some other protocol (rather than RARP) that would do the same thing as what ARP/RARP does. So, this SEND_RARP request could give the vhost-user backend a chance to format its own announce packet and broadcast (in the SEND_RARP request, the guest's mac address will be appended). CCing Victor to better know the truth... Peter
