Dear all,

Thank you, I will try this tomorrow. Keep you informed.

Regards,
Florian

On Thu, Sep 20, 2012 at 8:11 PM, David Boyes <[email protected]> wrote:

> Can't test this at the moment, but do the system logs tell you if the
> relocation generates a disconnect/reconnect event for the interface in
> question? IMHO, if it doesn't, then it should, since you're doing the
> equivalent of unplugging the machine, moving it, and then reconnecting it.
> Even if it's reconnecting to the same VLAN, the initial ARP to make sure
> you own the associated IP address should happen to avoid a race where a
> duplicate IP address could come online during the migration.
>
> Try running arping on the Linux machine via the 3270 console after the
> migration. If that fixes the problem (and it probably will), configure your
> Linux guests to generate a gratuitous ARP when the network interface state
> changes. That should force the FW to forget the old ARP entry and pickup
> the new one. Why the gratuitous ARP is no longer the default is still a
> mystery (at least to me, anyway) -- I can't conceive of a case where this
> would be the wrong behavior, and a ARP flood is not likely to be caused by
> a loose connector in this scenario (all virtual, all the time).
>
> There is probably a good argument that the VM migration code could/should
> force a proxy ARP for a guest when it gets migrated, though. It has enough
> information to do it (the old and new virtual MACs and the associated real
> OSA MACs) and that would at least force other devices to reevaluate any
> caches that might be present, even if the result ends up with the original
> configuration.
>
> Worth a call to the support center to discuss, anyway.
>
>


--
Best regards

Florian Bilek

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