[virt-tools-list] virt-xml/start: Temporarily use another boot configuration

[Cole Robinson]

On 2/12/19 3:46 AM, Marc Hartmayer wrote:
> On Thu, Jan 10, 2019 at 06:42 PM +0100, Cole Robinson <crobinso at redhat.com> wrote:
>> On 01/09/2019 06:41 AM, Marc Hartmayer wrote:
>>> On Wed, Dec 12, 2018 at 10:16 AM +0100, Marc Hartmayer <mhartmay at linux.ibm.com> wrote:
>>>> On Tue, Dec 11, 2018 at 08:22 PM +0100, Cole Robinson <crobinso at redhat.com> wrote:
> 
> […snip…]
> 
>>
>> No objections, indeed if you want general purpose edit+start then
>> extending virt-xml is the place to improve things.
>>
>> Originally it was a design decision to have virt-xml only operate on
>> single blocks of XML classes at a time. This is fixable but things get
>> ambiguous. Consider currently editing cpu, you'll do
>>
>>    virt-xml $VM --edit --cpu FOO
> 
> Thanks for the feedback!
> 
> How should 'virt-xml $VM --edit target=vda --disk="boot_order=1" --start'
> command behave?
> 
>  1. only start the domain (=> creation of a transient domain)?
>  2. or shall it also define the domain (=> definition + start)?
> 
> In case 1, there would already be a way to enforce the definition of
> this domain:
> 
> virt-xml $VM --edit target=vda --disk="boot_order=1" --start --define
> 
> For a start only, in case 2, we have to introduce an additional flag
> (e.g. '--no-define') to ensure that no definition takes place (=>
> transient domain):
> 
> e.g.
> 
> virt-xml $VM --edit target=vda --disk="boot_order=1" --start --no-define
> 
> Which of these do you prefer?

I think --no-define is good. We have --transient in virt-install but it
would be ambiguous in the virt-xml context (does it make the VM suddenly
transient?). Maybe something like --start-once but that's not any more
clear. So sounds like:

--start == --start --define == CreateXML() + DefineXML()
--start --no-define == CreateXML()

Thanks,
Cole