From: Paolo Bonzini <pbonzini@redhat.com>
To: Eric Blake <eblake@redhat.com>, Xiongzi Ge <gexxx132@umn.edu>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Live Migration with different block devices
Date: Tue, 24 Jun 2014 22:47:09 +0200 [thread overview]
Message-ID: <53A9E3CD.9010503@redhat.com> (raw)
In-Reply-To: <53A9E266.8080506@redhat.com>
Il 24/06/2014 22:41, Eric Blake ha scritto:
>> >
>> > I am trying to do migration with two different block devices in the source
>> > and destination hosts. For example, in the source the data in /dev/vda
>> > are 'aaaaa'. The guest has a cache. These data are cached. In the other
>> > host, the data in this device are 'bbbbb'. If we do migration, I want
>> > the guest vm recognize this change. How does qemu deal with the cache
>> > data? Thanks.
> If you want the guest to see different disk contents, then hotunplug the
> original and hotplug in the new disk. Migration is NOT supposed to
> change disk contents. Your problem is independent of migration.
Or if you really do not want to do that, all access to the disk has to
be done with O_DIRECT in the guest.
Paolo
next prev parent reply other threads:[~2014-06-24 20:47 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-24 19:18 [Qemu-devel] Live Migration with different block devices Xiongzi Ge
2014-06-24 19:37 ` Paolo Bonzini
2014-06-24 19:55 ` Xiongzi Ge
2014-06-24 20:25 ` Paolo Bonzini
2014-06-24 20:34 ` Xiongzi Ge
2014-06-24 20:41 ` Eric Blake
2014-06-24 20:47 ` Paolo Bonzini [this message]
2014-06-24 21:26 ` Xiongzi Ge
2014-06-24 21:39 ` Christopher Covington
-- strict thread matches above, loose matches on Subject: below --
2014-06-24 19:22 Xiongzi Ge
2014-06-24 21:29 ` Brian Jackson
2014-06-24 23:16 ` Eric Blake
2014-06-25 0:08 ` Xiongzi Ge
2014-06-25 2:10 ` Eric Blake
2014-06-25 6:18 ` Paolo Bonzini
2014-06-25 14:14 ` Xiongzi Ge
2014-06-25 14:18 ` Paolo Bonzini
2014-06-25 14:32 ` Xiongzi Ge
2014-06-25 14:39 ` Paolo Bonzini
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