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How to customize libvirt.xml for an instance ?

Hello

I'm following the procedure at https://ask.openstack.org/en/question/5415/customize-libvirtxml-for-an-instance/ but it doesn't seem to work. I'm on Havana.

This is what I see:

(1) No instance on the compute node

    root@node-12:~# virsh
    Welcome to virsh, the virtualization interactive terminal.

    Type:  'help' for help with commands
           'quit' to quit

virsh # list
 Id    Name                           State
----------------------------------------------------

(2) Create and boot an instance via Horizon, find the libvirt file and check it

virsh # list
 Id    Name                           State
----------------------------------------------------
 20    instance-0000000d              running

virsh #

root@node-12:~# ls -la /var/lib/nova/instances/
total 8
drwxr-xr-x  6 nova nova  136 Apr 12 11:50 .
drwxr-xr-x 10 nova nova  123 Mar 31 11:18 ..
drwxr-xr-x  2 nova nova   53 Apr 12 11:51 760a2891-da1a-40e1-b6de-ef6b9f029b09
more /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
    <system>
      <entry name="manufacturer">OpenStack Foundation</entry>
      <entry name="product">OpenStack Nova</entry>
      <entry name="version">2013.2.2</entry>
      <entry name="serial">d289170a-baff-42d0-b858-2268192cc682</entry>
      <entry name="uuid">760a2891-da1a-40e1-b6de-ef6b9f029b09</entry>
    </system>

(3) Modify the libvirt file of the instance ( changed the value of entry name "product" ) and save the file

more /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
<system>
      <entry name="manufacturer">OpenStack Foundation</entry>
      <entry name="product">Router in OpenStack Nova</entry>
      <entry name="version">2013.2.2</entry>
      <entry name="serial">d289170a-baff-42d0-b858-2268192cc682</entry>
      <entry name="uuid">760a2891-da1a-40e1-b6de-ef6b9f029b09</entry>
    </system>

(4) Follow the procedure explained at https://ask.openstack.org/en/question/5415/customize-libvirtxml-for-an-instance/

virsh # destroy instance-0000000d
Domain instance-0000000d destroyed

virsh # undefine instance-0000000d
Domain instance-0000000d has been undefined

virsh # define /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
Domain instance-0000000d defined from /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml

virsh # start instance-0000000d
Domain instance-0000000d started

virsh # exit

(5) Check that the libvirt file is still modified, and then soft reboot (via Horizon) the instance

more /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
    <system>
      <entry name="manufacturer">OpenStack Foundation</entry>
      <entry name="product">Router in OpenStack Nova</entry>
      <entry name="version">2013.2.2</entry>
      <entry name="serial">d289170a-baff-42d0-b858-2268192cc682</entry>
      <entry name="uuid">760a2891-da1a-40e1-b6de-ef6b9f029b09</entry>
    </system>

( soft reboot via Horizon )

(6) After soft reboot check the libvirt file; entry name "product" is back to the original value

more /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
    <system>
      <entry name="manufacturer">OpenStack Foundation</entry>
      <entry name="product">OpenStack Nova</entry>
      <entry name="version">2013.2.2</entry>
      <entry name="serial">d289170a-baff-42d0-b858-2268192cc682</entry>
      <entry name="uuid">760a2891-da1a-40e1-b6de-ef6b9f029b09</entry>
    </system>

Of course I don't really care about changing the entry name "product", but this is just to show that even what I believe was a cosmetic change is not possible (at least in my scenario)

Any suggestion ? Anybody able to reproduce the same behavior ?

E.

How to customize libvirt.xml for an instance ?

Hello

I'm following the procedure at https://ask.openstack.org/en/question/5415/customize-libvirtxml-for-an-instance/ but it doesn't seem to work. I'm on Havana.

This is what I see:

(1) No instance on the compute node

    root@node-12:~# virsh
    Welcome to virsh, the virtualization interactive terminal.

    Type:  'help' for help with commands
           'quit' to quit

virsh # list
 Id    Name                           State
----------------------------------------------------

(2) Create and boot an instance via Horizon, find the libvirt file and check it

virsh # list
 Id    Name                           State
----------------------------------------------------
 20    instance-0000000d              running

virsh #

root@node-12:~# ls -la /var/lib/nova/instances/
total 8
drwxr-xr-x  6 nova nova  136 Apr 12 11:50 .
drwxr-xr-x 10 nova nova  123 Mar 31 11:18 ..
drwxr-xr-x  2 nova nova   53 Apr 12 11:51 760a2891-da1a-40e1-b6de-ef6b9f029b09
more /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
    <system>
      <entry name="manufacturer">OpenStack Foundation</entry>
      <entry name="product">OpenStack Nova</entry>
      <entry name="version">2013.2.2</entry>
      <entry name="serial">d289170a-baff-42d0-b858-2268192cc682</entry>
      <entry name="uuid">760a2891-da1a-40e1-b6de-ef6b9f029b09</entry>
    </system>

(3) Modify the libvirt file of the instance ( changed the value of entry name "product" ) and save the file

more /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
<system>
      <entry name="manufacturer">OpenStack Foundation</entry>
      <entry name="product">Router in OpenStack Nova</entry>
      <entry name="version">2013.2.2</entry>
      <entry name="serial">d289170a-baff-42d0-b858-2268192cc682</entry>
      <entry name="uuid">760a2891-da1a-40e1-b6de-ef6b9f029b09</entry>
    </system>

(4) Follow the procedure explained at https://ask.openstack.org/en/question/5415/customize-libvirtxml-for-an-instance/

virsh # destroy instance-0000000d
Domain instance-0000000d destroyed

virsh # undefine instance-0000000d
Domain instance-0000000d has been undefined

virsh # define /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
Domain instance-0000000d defined from /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml

virsh # start instance-0000000d
Domain instance-0000000d started

virsh # exit

(5) Check that the libvirt file is still modified, and then soft reboot (via Horizon) the instance

more /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
    <system>
      <entry name="manufacturer">OpenStack Foundation</entry>
      <entry name="product">Router in OpenStack Nova</entry>
      <entry name="version">2013.2.2</entry>
      <entry name="serial">d289170a-baff-42d0-b858-2268192cc682</entry>
      <entry name="uuid">760a2891-da1a-40e1-b6de-ef6b9f029b09</entry>
    </system>

( soft reboot via Horizon )

(6) After soft reboot check the libvirt file; entry name "product" is back to the original value

more /var/lib/nova/instances/760a2891-da1a-40e1-b6de-ef6b9f029b09/libvirt.xml
    <system>
      <entry name="manufacturer">OpenStack Foundation</entry>
      <entry name="product">OpenStack Nova</entry>
      <entry name="version">2013.2.2</entry>
      <entry name="serial">d289170a-baff-42d0-b858-2268192cc682</entry>
      <entry name="uuid">760a2891-da1a-40e1-b6de-ef6b9f029b09</entry>
    </system>

Of course I don't really care about changing the entry name "product", but this is just to show that even what I believe was a cosmetic change is not possible (at least in my scenario)

Any suggestion ? Anybody able to reproduce the same behavior ?

E.