From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Xu <peterx@redhat.com>
Subject: Re: [PATCH 0/4 for 2.3] vhost-user live migration support
Date: Mon, 14 Dec 2015 21:00:22 +0800
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Cc: dev@dpdk.org, Victor Kaplansky <victork@redhat.com>,
 "Michael S. Tsirkin" <mst@redhat.com>
To: Yuanhan Liu <yuanhan.liu@linux.intel.com>
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On Mon, Dec 14, 2015 at 08:09:37PM +0800, Yuanhan Liu wrote:
> It seems that we have exactly the same test environment set up: I have
> one server (where I normally do vhost test there) and one desktop (my
> dev box), 
> 
> On both hosts, there is an ovs bridge, with IP address 192.168.100.1
> assigned manually. Later, I started a VM on the server, and manually
> assigned IP to 192.168.100.10. I then run "ping 192.168.100.1" for
> live migration testing.
> 
> The migration to my desktop somehow works (even though there are some
> bugs in this patch set), however, I did see what Pavel saw: about 12
> packets has been lost, which means about 12 seconds the network is not
> working well.

Hi, Yuanhan,

I _guess_ the problem for ping might be: guest ARP entry for
192.168.100.1 is not updated. Or say, after guest migrated to host2
from host1, guest is still trying to send packet to host1's NIC (no
one is telling it to update, right?), so no one is responding the
ping. When the entry is expired, guest will resend the ARP request,
and host2 will respond this time, with mac address on host2 provided
this time. After that, ping works again.

(not familiar with OVS too, so am just taking it as a "vritual"
switch)

Thanks.
Peter