[Libguestfs] [Bug 1381502] virt-sparsify doesn't remove content of deleted files on XFS

[Richard W.M. Jones]

On Tue, Oct 04, 2016 at 02:36:53PM +0000, MUCHOWSKI, Piotr (EXT - PL) wrote:
> Good afternoon Richard,
>
> Just one question about "--scrub" option. Can the "scrub mode" be
> enabled globally (not just for single FILE after this option)?
> Preferably for all sysprep items where some files are deleted. For
> example logfiles rh-subscription-manager rhn-systemid and so on.

No, it doesn't work this way.  You have to scrub individual files.
Note this uses the 'scrub(1)' command.

> And finally, is any requirement the CentOS/RedHat images must be
> processed by virt-sysprep running on CentOS host and not on Ubuntu
> (which has different kernel). Because what I observed, these tools
> get the host kernel from /boot directory. I didn't found how to
> provide arbitrary kernel file or use the kernel built in processed
> image.

You can use a different kernel by setting SUPERMIN_* environment
variables:

http://libguestfs.org/supermin.1.html#USING-A-CUSTOM-KERNEL-AND-KERNEL-MODULES
http://libguestfs.org/guestfs-faq.1.html#how-can-i-compile-and-install-libguestfs-if-my-distro-doesnt-have-new-enough-qemu-supermin-kernel

In theory you could extract the kernel from the disk image using
'virt-get-kernel'.  It doesn't currently let you extract the modules
from the same disk image [that would be a nice feature], but you could
do that with a trivial bit of guestfish scripting.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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