[libvirt] [PATCH v1 00/11] Rework storage migration

[Paolo Bonzini]

Il 28/11/2012 15:46, Daniel P. Berrange ha scritto:
> On Wed, Nov 28, 2012 at 03:43:16PM +0100, Paolo Bonzini wrote:
>> Il 28/11/2012 11:59, Daniel P. Berrange ha scritto:
>>> If the user has requested TUNNELLED migration, we need follow up work done.
>>> We need the NBD server to be able to accept a pre-opened file descriptor
>>> to rather than listening on a TCP host/port,
>>
>> This is already supported.  However, the pre-opened fd would be for a
>> listening socket.
>>
>> The main problem is that even though a single port is used on the
>> destination, it is used for multiple connections.  Migration would
>> require an arbitrary number of streams, and I'm afraid supporting this
>> would basically entail rewriting all the tunnelling code.
> 
> Hmm, yes, that is rather a complex problem.
> 
> I've long thought that QEMU migration should have a mode where it passes
> all its data through TLS natively. So you could do secure migration,
> without needing to use libvirtd tunnelling.

I agree.  Hopefully, the various rewrites/refactorings of the upstream
migration code will make this easier.

> The same is really true of the NBD code. I know the "official" NBD
> impl does not do encryption, but there's no strong reason why QEMU
> can't layer in TLS below the NBD protocol if it is an explicit
> opt-in at both client+server requested by libvirt. That would at
> least solve the security issue, without requiring tunnelling.

Yes, that's a good idea.

Paolo