[openib-general] Unicast ARP

[Michael S. Tsirkin]

Hello!
Quoting r. Roland Dreier (roland at topspin.com) "Re: [openib-general] Unicast ARP":
>     Hal> Is this restricted to LID changes or apply more generally to
>     Hal> hardware address (GID and/or QPN) changes ? (I had seen
>     Hal> something similar when the QPN changed; ARP timeout/retries
>     Hal> are needed prior to connectivity being restored).
> 
> Just LID changes.  If GID or QPN changes, then the HW address is
> different and the kernel neighbour code can notice.  It's just like an
> IP address moving to a different MAC on ethernet: either the old ARP
> entry has to time out, or the interface with the new address has to
> send a gratuitous ARP.


Currently it also seems that by just bringing the interface up
and down the hw address will change.
Unless I am doing something wrong, this inconvenience seems
to be caused by a different QP number being assigned.
Cant this be solved e.g. by assigning a fixed QP number
for IP over IB?

Thanks,
MST