[libvirt] virt-install ERROR Host does not support any virtualization options

[Michal Privoznik]

On 01/02/2018 12:57 PM, Mihamina RAKOTOMANDIMBY wrote:
> Hello,
> 
> I face this problem and I am willing to provide a patch in order to have
> a more informative message.
> This, of course with our help. I am not quite certain.
> 
> First of all: What is the problem?
> 
> On a fresh Install (ArchLinux for me), if ever forget to install Qemu
> and launch "virt-install" with "--type kvm", I get the message:
> 
> "Host does not support any virtualization options"
> 
> 
> According to me, this message should be improved: if Qemu is not found,
> this should be "Did not find Qemu, please install it".
> 
> As I searched, the message is generated by this piece of code:
> 
> https://github.com/virt-manager/virt-manager/blob/c92aade081687b19f5a60cddfe331b2fb6d09f98/virtinst/capabilities.py#L390
> 
> 
> As I write now, I cant find the pice of code actually calling the
> "quemu" binary. I think I should add a try/catch block there and Raise
> the right Exception.
> Would someone help me a bit?

virt-manager is not calling any qemu binaries at all. It just relies on
whatever capabilities libvirt presents. The reason for that is remote
access - just imagine you'd be installing a domain on a remote machine
and virt-manager (virt-install) would spawn your local qemu binary to
find out its capabilities. That would be flawed, wouldn't it.

I agree that the error message can be made better (just like 90% of
other messages of ours), but first things first. What's the output of
'virsh capabilities' (if you're giving any connection URI to
virt-install give it to virsh too).

Michal