Re: [Qemu-block] [Qemu-devel] storing machine data in qcow images?

[Richard W.M. Jones]

On Wed, Jun 06, 2018 at 01:02:53PM +0200, Max Reitz wrote:
> (I'm wondering if we could write a block driver that could provide such
> a chunk allocation transparently to qcow2...  Note that a qcow2 file
> does not need to be continuous, so you could in theory indeed store the
> qcow2 file and its data in completely separate places in a tar file.)

nbdkit-split-plugin
(https://github.com/libguestfs/nbdkit/tree/master/plugins/split).  It
currently doesn't support resizing although it could do fairly easily.

> Yeah, but why make qcow2 that format?  That's what I completely fail to
> understand.

I started off a long reply here, but I think you're right.  If we
cannot make people decide on and use a proper disk image + metadata
container, then it's also unlikely we'll get them to add sensible
metadata to their qcow2 images either :-(

Rich.

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