something (qemu?) is leaking

[lejeczek]

On 23/05/2022 11:03, Michal Prívozník wrote:
> On 5/23/22 11:19, lejeczek wrote:
>> Hi guys.
>>
>> I do a simple thing which should be easy to reproduce.
>>
>> -> $ virt-install -n rum1 --virt-type kvm --os-variant centos8 --memory
>> $((4*1024)) --disk=/VMs3/rum1.qcow2,device=disk,bus=virtio --network
>> network=10_3_1,model=virtio --graphics=listen=0.0.0.0 --cpu EPYC-Rome
>> --vcpus 3 --cdrom /VMs3/CentOS-Stream-9-latest-x86_64-dvd1.iso
>>
>> During manual setup in the VM I set 'hostname' to something and when
>> installation begins and disk config stage takes place I can see - and
>> later when VM(c9s) is ready can confirm - that VG name is taken from
>> another VM defined/running on the host.
> I'm no LVM expert, but I always thought that installer has some defaults
> built in and thus it's kind of expected if you went with defaults.
>
> But I'm kind of failing why is this a problem since all you're giving to
> the guest is a single qcow2 disk which is not shared between two
> domains. Maybe I'm misunderstanding something?
>
> Michal
>
I did one type there in, it should have been:
... During manual setup in the VM _if_ I _do not_ set 
'hostname' to something

It's a critical problem - when something leaks - the 
VM/guest ended up "knowing" about other VMs on the host.

Those are simple defaults for disk part of the install process:
When 'hostname' is set by a user then VG  gets name from 
installer set to eg. 'cs_hostname'.
When that 'hostname' is not set then it should be just 'cs'

I have a newly installed, clean VM with VG of 
'cs_other-guest-on-this-host' - somehow that new VM "knew" 
about other guest on the host - it happened twice, two 
installation as with above cmd, each time with new guest's 
VG name of hostname of a already existing, different guest, 
each time different guest.

thanks, L.