[virt-tools-list] [PATCH virt-install] virtinst: Add --transient flag.

[Pavel Hrdina]

On Thu, Jun 02, 2016 at 11:02:27AM +0100, Richard W.M. Jones wrote:
> On Thu, Jun 02, 2016 at 11:00:16AM +0200, Pavel Hrdina wrote:
> > We should forbid to use --transient with all other types of install
> > methods because it doesn't make any sense and it doesn't work.
> > Unfortunately we need to add a check "if options.transient and
> > (options.pxe or options.cdrom or ....), we cannot simply check for
> > --import or --boot because --boot can be combined with any other
> > install method.
> 
> I'm not sure I understand.  Surely a --pxe install (for example) could
> involve a boot, and so --transient could be appropriate?
> 
> What other options are in the list elided above?

The thing is that virt-install has 2 phases while installing and each phase has
its own XML.  The first phase is the install phase where install XML is used.
After the installation is completed virt-install destroys the guest, replace the
domain XML with boot XML and starts it again.

If you set that the domain is transient, the domain disappears after the first
phase is completed.  Which leads to two different solutions:

1. allow --transient only with --import or --boot but not with other install
options, because they redefine the domain XML

2. update the code so also all other install option would be able to destroy the
guest and start it again only as transient.  Currently it doesn't work.  If you
use --noautoconsole or kill the virt-install during first phase there is no
process that will start the guest again and if you let the virt-install to start
the guest again it will fail with error message that the domain cannot be found.

Pavel