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Re: [Xen-devel] Does XEN have any hot backup/snapshot features or plan?

To: zign <zign@xxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] Does XEN have any hot backup/snapshot features or plan?
From: Brendan Cully <brendan@xxxxxxxxx>
Date: Sun, 5 Apr 2009 17:24:41 -0700
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On Monday, 06 April 2009 at 09:16, zign wrote:
> Mr Brendan Cully,
> Thank you for your fast reply!
> LVM + checkpoint sounds reasonable, but there is problem:
> if the storage and the MEM checkpoint are not saved in the
> very same time, I am not sure if this is a "correct" snapshot.
> You mentioned something about the migration hook that can tie
> the MEM checkpoint and the LVM snapshot together. Can this
> migration hook ensure that there is no "time-shift" between the
> MEM and storage?

As you say, the memory and disk images must be synchronized, and you
can use the external device migration hook to do it. I posted some
demo (that is, not production!) code to do it here:


But I haven't looked at this problem in quite some time.

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