Save virtual machine state?

[Loren Rogers]

I'm sure this has already been discussed, but is there a way to save the state of a virtual machine, instead of shutting it down? I can't find any info in the docs on what exactly pausing a VM does, but could this be similar?

Thanks

[Chris Laprise]

Pausing is only in-memory stopping of the VM. Un-pausing makes the VM
continue running.

Qubes doesn't (yet) support saving to disk like hibernate. If this ever
does become a feature it will probably be for use with HVMs in Qubes 4.x.

--

Chris Laprise, tas...@posteo.net
https://github.com/tasket
https://twitter.com/ttaskett
PGP: BEE2 20C5 356E 764A 73EB 4AB3 1DC4 D106 F07F 1886

[Loren Rogers]

-------- Original Message --------

On January 25, 2018 9:54 AM, Chris Laprise <tas...@posteo.net> wrote:

>On 01/24/2018 10:33 PM, Loren Rogers wrote:
>>I'm sure this has already been discussed, but is there a way to save the
>> state of a virtual machine, instead of shutting it down? I can't find
>> any info in the docs on what exactly pausing a VM does, but could this
>> be similar?
>>Thanks
>>
>
> Pausing is only in-memory stopping of the VM. Un-pausing makes the VM
> continue running.
>
> Qubes doesn't (yet) support saving to disk like hibernate. If this ever
> does become a feature it will probably be for use with HVMs in Qubes 4.x.
>
>
>

> Chris Laprise, tas...@posteo.net
>https://github.com/tasket
>https://twitter.com/ttaskett
> PGP: BEE2 20C5 356E 764A 73EB 4AB3 1DC4 D106 F07F 1886
>

Thanks Chris - good to know.
​

[Vít Šesták]

On pausing: Remember that there are some issues. For example, the VMs resume after sleep&resume. Also, it seems it does not work well with changes of monitor configuration.

On hibernation: This can work with standalone VMs, but it is problematic by design on template-based (although probably possible) VMs. once you hibernate a VM, you need to remember all the state, including the root filesystem. Unlike traditional systems, the root device can be updated outside the VM, just by running the TemplateVM. In such case, Qubes has to ensure that the VM won't see the changes before reboot. Qubes has some ways to achieve this for running VMs (you see, you don't need to shut the template-based VMs down when updating the template), but it probably degrades some performance. Having to maintain it for some forgotten hibernated VMs would be some unexpected source of performance hit. So, it would be probably technically feasible (though maybe not easy), but hard for UX.

Regards,
Vít Šesták 'v6ak'