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

Tue Jan 17 17:46:43 UTC 2012
James B. Byrne <byrnejb at harte-lyne.ca>

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'>
  <name>vm-centos-6</name>
  <uuid>77692b36-d424-175f-b991-abc58fa0359b</uuid>
  <description>vm clone prototype
root user password: protoype</description>
  <memory>2097152</memory>
  <currentMemory>2097152</currentMemory>
  <vcpu>1</vcpu>
  <os>
    <type arch='x86_64' machine='rhel6.0.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pae/>
  </features>
  <clock offset='utc'/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none'/>
      <source dev='/dev/vg_vhost01/lv_vm_base'/>
      <target dev='vda' bus='virtio'/>
      <alias name='virtio-disk0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x05' function='0x0'/>
    </disk>
    <disk type='block' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <target dev='hdc' bus='ide'/>
      <readonly/>
      <alias name='ide0-1-0'/>
      <address type='drive' controller='0' bus='1' unit='0'/>
    </disk>
    <controller type='ide' index='0'>
      <alias name='ide0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x1'/>
    </controller>
    <interface type='bridge'>
      <mac address='52:54:00:28:7e:ce'/>
      <source bridge='br0'/>
      <target dev='vnet5'/>
      <model type='virtio'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x03' function='0x0'/>
    </interface>
    <serial type='pty'>
      <source path='/dev/pts/6'/>
      <target port='0'/>
      <alias name='serial0'/>
    </serial>
    <console type='pty' tty='/dev/pts/6'>
      <source path='/dev/pts/6'/>
      <target type='serial' port='0'/>
      <alias name='serial0'/>
    </console>
    <input type='tablet' bus='usb'>
      <alias name='input0'/>
    </input>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='5905' autoport='yes'/>
    <sound model='ac97'>
      <alias name='sound0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x04' function='0x0'/>
    </sound>
    <video>
      <model type='cirrus' vram='9216' heads='1'/>
      <alias name='video0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x02' function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <alias name='balloon0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x06' function='0x0'/>
    </memballoon>
  </devices>
  <seclabel type='dynamic' model='selinux' relabel='yes'>
    <label>system_u:system_r:svirt_t:s0:c299,c322</label>
    <imagelabel>system_u:object_r:svirt_image_t:s0:c299,c322</imagelabel>
  </seclabel>
</domain>

virsh #

A substantially identical clone of the prototype.  This
guest has had no additional storage added to it.

virsh # dumpxml sshpipe.harte-lyne.ca
<domain type='kvm' id='19'>
  <name>sshpipe.harte-lyne.ca</name>
  <uuid>5fbd2bad-059c-da0d-c856-c16cfb831a9a</uuid>
  <description>vm clone prototype
root user password: protoype</description>
  <memory>2097152</memory>
  <currentMemory>2097152</currentMemory>
  <vcpu>1</vcpu>
  <os>
    <type arch='x86_64' machine='rhel6.0.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pae/>
  </features>
  <clock offset='utc'/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none'/>
      <source
dev='/dev/vg_vhost01/lv_vm_sshipe.harte-lyne.ca_00'/>
      <target dev='vda' bus='virtio'/>
      <alias name='virtio-disk0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x05' function='0x0'/>
    </disk>
    <disk type='block' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <target dev='hdc' bus='ide'/>
      <readonly/>
      <alias name='ide0-1-0'/>
      <address type='drive' controller='0' bus='1' unit='0'/>
    </disk>
    <controller type='ide' index='0'>
      <alias name='ide0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x1'/>
    </controller>
    <interface type='bridge'>
      <mac address='52:54:00:ee:d8:32'/>
      <source bridge='br0'/>
      <target dev='vnet2'/>
      <model type='virtio'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x03' function='0x0'/>
    </interface>
    <serial type='pty'>
      <source path='/dev/pts/3'/>
      <target port='0'/>
      <alias name='serial0'/>
    </serial>
    <console type='pty' tty='/dev/pts/3'>
      <source path='/dev/pts/3'/>
      <target type='serial' port='0'/>
      <alias name='serial0'/>
    </console>
    <input type='tablet' bus='usb'>
      <alias name='input0'/>
    </input>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='5902' autoport='yes'/>
    <sound model='ac97'>
      <alias name='sound0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x04' function='0x0'/>
    </sound>
    <video>
      <model type='cirrus' vram='9216' heads='1'/>
      <alias name='video0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x02' function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <alias name='balloon0'/>
      <address type='pci' domain='0x0000' bus='0x00'
slot='0x06' function='0x0'/>
    </memballoon>
  </devices>
  <seclabel type='dynamic' model='selinux' relabel='yes'>
    <label>system_u:system_r:svirt_t:s0:c876,c1002</label>
    <imagelabel>system_u:object_r:svirt_image_t:s0:c876,c1002</imagelabel>
  </seclabel>
</domain>

virsh #


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

and this for vgdisplay

[root at sshpipe ~]# vgdisplay
  Couldn't find device with uuid
umrIn6-Np0c-NC4Z-MuUo-5TBj-IKRE-XBU0De.
  --- Volume group ---
  VG Name               vg_vm_centos_6
  System ID
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  7
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                3
  Open LV               2
  Max PV                0
  Cur PV                2
  Act PV                1
  VG Size               38.57 GiB
  PE Size               4.00 MiB
  Total PE              9873
  Alloc PE / Size       8018 / 31.32 GiB
  Free  PE / Size       1855 / 7.25 GiB
  VG UUID
qa6jwq-5gTp-6mMH-IWl9-OrEK-HjWc-pbaFsa

But, sshpipe should only have a single 8Gb VirtIO disk
assigned.

-- 
***          E-Mail is NOT a SECURE channel          ***
James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
Harte & Lyne Limited          http://www.harte-lyne.ca
9 Brockley Drive              vox: +1 905 561 1241
Hamilton, Ontario             fax: +1 905 561 0757
Canada  L8E 3C3


-- 
***          E-Mail is NOT a SECURE channel          ***
James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
Harte & Lyne Limited          http://www.harte-lyne.ca
9 Brockley Drive              vox: +1 905 561 1241
Hamilton, Ontario             fax: +1 905 561 0757
Canada  L8E 3C3