[CentOS-virt] [CentOS] VirtIO disk 'leakage' across guests?

Fri Jan 20 16:01:26 UTC 2012
James B. Byrne <byrnejb at harte-lyne.ca>

On Tue, January 17, 2012 16:01, Dennis Jacobfeuerborn wrote:
> On 01/17/2012 06:46 PM, James B. Byrne wrote:
>>
>> On Mon, January 16, 2012 17:01, Dennis Jacobfeuerborn
>> wrote:
>>> On 01/16/2012 10:16 PM, James B. Byrne wrote:
>>>
>>> ...
>>>> The xmldump for this guest instance contains this:
>>> ...
>>>
>>> Please post the xmldumps of the original guest and
>>> cloned
>>> guest right after
>>> cloning and without any modifications.
>>>
>>> Regards,
>>>     Dennis
>>
>> Prototype dumpxml
>>
>> virsh # dumpxml vm-centos-6
>> <domain type='kvm' id='34'>
> ...
>>        <source dev='/dev/vg_vhost01/lv_vm_base'/>
>> </domain>
>
>> virsh # dumpxml sshpipe.harte-lyne.ca
>> <domain type='kvm' id='19'>
> ...
>>        <source
>> dev='/dev/vg_vhost01/lv_vm_sshipe.harte-lyne.ca_00'/>
>> </domain>
>>
>> The second guest, sshpipe, shows this for pvdisplay:
>>
>> [root at sshpipe ~]# pvdisplay
>>    Couldn't find device with uuid
>> umrIn6-Np0c-NC4Z-MuUo-5TBj-IKRE-XBU0De.
>>    --- Physical volume ---
>>    PV Name               /dev/vda2
>>    VG Name               vg_vm_centos_6
>>    PV Size               7.32 GiB / not usable 3.00 MiB
>>    Allocatable           yes (but full)
>>    PE Size               4.00 MiB
>>    Total PE              1874
>>    Free PE               0
>>    Allocated PE          1874
>>    PV UUID
>> djM23m-6Yeb-BQ2x-gPh9-ORMt-dX2i-Ou9xBQ
>>
>>    --- Physical volume ---
>>    PV Name               unknown device
>>    VG Name               vg_vm_centos_6
>>    PV Size               31.25 GiB / not usable 3.97 MiB
>>    Allocatable           yes
>>    PE Size               4.00 MiB
>>    Total PE              7999
>>    Free PE               1855
>>    Allocated PE          6144
>>    PV UUID
>> umrIn6-Np0c-NC4Z-MuUo-5TBj-IKRE-XBU0De
>>
>
> What does the first guest say for pvdisplay?
> The key here is the PV UUID "umrIn6-Np0c...". Either this
> PV must exists
> somewhere else on the host or in one of the guest or maybe
> the cloning
> process has corrupted the LVM metadata.


I finally found the time to check for this UUID on the kvm
host and I find it referenced in these files:

/etc/lvm/archive/vg_vm_centos_6_00003-2133754855.vg:      
             id = "umrIn6-Np0c-NC4Z-MuUo-5TBj-IKRE-XBU0De"
/etc/lvm/archive/vg_vm_centos_6_00002-2048459897.vg:      
             id = "umrIn6-Np0c-NC4Z-MuUo-5TBj-IKRE-XBU0De"
/etc/lvm/archive/vg_vm_centos_6_00004-568234656.vg:       
             id = "umrIn6-Np0c-NC4Z-MuUo-5TBj-IKRE-XBU0De"
/etc/lvm/backup/vg_vm_centos_6:                 id =
"umrIn6-Np0c-NC4Z-MuUo-5TBj-IKRE-XBU0De"

Now, by my way of thinking, as vg_vm_centos_6 is the
volume group originally assigned to the prototype guests
when it was created from the install dvd then it should
not exist in the vhost01 file system at all.  Am I
correct?

I cannot see any other vgs for guests that were created by
a dvd style install.

I have shutdown the affected guests and have installed new
guests with different names from dvd media to take over
the functions of those guests exhibiting the disk/lv cross
linkage problem.

What would happen if I simply deleted the files containing
vg_vm-centos_6 in their name from the kvm host?  These
exist only in /etc/lvm/archive and /etc/lvm/backup.




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James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
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