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RE: [Xen-devel] arp during live migration

To: "Jacob Gorm Hansen" <jacobg@xxxxxxx>
Subject: RE: [Xen-devel] arp during live migration
From: "Graham, Simon" <Simon.Graham@xxxxxxxxxxx>
Date: Sat, 3 Mar 2007 12:10:10 -0500
Cc: Cristian Zamfir <zamf@xxxxxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx
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Thread-topic: [Xen-devel] arp during live migration
> When I was last doing this with self-migration, I would resend the ARP
> reply several times after arrival, as in any case the packet may get
> lost due to a collision etc. This is pretty trivial with
> because is controlled by a guest userspace program -- I suppose that
> doing it in netfront would require a short-lived kernel thread. Or
> perhaps this should just all be handled by dom0, since we are talking
> hosted migration anyway. Actually, having netfront send out protocol
> dependent packets is quite ugly, and makes netfront depend on IP being
> enabled, which is all wrong (see link error below when disabling IP in
> xenlinux).

I understand that the gratuitous ARP could be lost (and probably should
be sent multiple times) _but_ I am currently seeing a 100% loss (the
packet simply never makes it to peth0 and out on the wire), so I think
there is an actual bug somewhere in the netfront<->netback<->bridge


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