Failure to alter VM's MAC address with virsh

Hi,

Thanks for reporting this bug and helping to make Ubuntu better.

Could you please say a bit more about what you are trying to do and what exactly you are expecting to happen?

You say

 'but the VM still does not connect to its host the way it is supposed to. '

How is it supposed to, and how is it actually doing it (i.e. actual xml for the libvirt network config and VM)?

$ virsh dumpxml myvm | grep address
      <mac address='52:54:00:fa:c8:17'/>
$ virsh detach-interface myvm bridge --mac '52:54:00:fa:c8:17'
error: operation failed: network device cannot be detached - device state missing
$ virsh attach-interface myvm bridge br0 --mac '00:16:3e:10:34:31'
Interface attached successfully
$ virsh dumpxml myvm | grep address
      <mac address='52:54:00:fa:c8:17'/>
      <mac address='00:16:3e:10:34:31'/>
$ virsh detach-interface myvm bridge --mac '52:54:00:fa:c8:17'
error: operation failed: network device cannot be detached - device state missing
$ virsh detach-interface myvm bridge --mac '00:16:3e:10:34:31'
Interface detached successfully
$ virsh net-list --all
Name State Autostart
-----------------------------------------

$ ping -c1 myvm
PING myvm.inside.mydomain.net (10.10.10.38) 56(84) bytes of data.
64 bytes from myvm.inside.mydomain.net (10.10.10.38): icmp_seq=1 ttl=64 time=12.7 ms

--- myvm.inside.mydomain.net ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 12.718/12.718/12.718/0.000 ms
$ virsh shutdown myvm
Domain myvm is being shutdown
$ virsh dumpxml myvm
<domain type='kvm'>
  <name>myvm</name>
  <uuid>594c38f9-bf5f-7cf2-53f4-d6d1d6fa0da3</uuid>
  <memory>524288</memory>
  <currentMemory>524288</currentMemory>
  <vcpu>1</vcpu>
  <os>
    <type arch='x86_64' machine='pc-0.12'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
  </features>
  <clock offset='utc'/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>destroy</on_crash>
  <devices>
    <emulator>/usr/bin/kvm</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/opt/vm/myvm/tmpQPc9uI.qcow2'/>
      <target dev='hda' bus='ide'/>
    </disk>
    <interface type='bridge'>
      <mac address='52:54:00:fa:c8:17'/>
      <source bridge='br0'/>
      <target dev='vnet7'/>
      <model type='virtio'/>
    </interface>
    <serial type='pty'>
      <target port='0'/>
    </serial>
    <console type='pty'>
      <target port='0'/>
    </console>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='-1' autoport='yes' listen='127.0.0.1'/>
    <video>
      <model type='cirrus' vram='9216' heads='1'/>
    </video>
  </devices>
</domain>

$

The problem is the inability to remove the original MAC address of a VM, whereas removing a 2nd MAC that was added with a "virsh attach-interface" works. Why is that?

Would it suffice to do:

   virsh edit myvm

and change the mac address in the definition? Note that if the mac address doesn't show up in the definition in the editor, you should be able to add it (using the mac address you want) and it will be respected the next time.

(I suspect the 'device state missing' message is wrong, and should actually read 'device busy')

[Expired for libvirt (Ubuntu) because there has been no activity for 60 days.]