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Date: Mon, 23 Nov 2009 16:30:20 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: [Qemu-devel] Re: Live migration protocol, device features,
	ABIs and   other beasts
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To: Gleb Natapov <gleb@redhat.com>
Cc: Juan Quintela <quintela@trasno.org>, qemu-devel@nongnu.org

On 11/23/2009 04:22 PM, Gleb Natapov wrote:
> As far as I remember the two general's problem talks about unreliable
> channel, not unreliable nodes. Why not having destination send ACK/NACK
> to the source when it knows that migration succeeded/failed. If source
> gets NACK it continues, if it gets ACK it exits, otherwise it stays in
> paused state. Yes, there are worst case scenarios where this will not work,
> but it will not be worse then what we have now.

Also, this can be done in a per-protocol manner.  TCP and Unix socket 
migration would support it, while exec (and maybe fd) migration would not.

Paolo