Description of problem:

I am working with an environment in which some nova instances are missing the "<nova:owner>" attribute in the embedded metadata in the domain xml. For example:

  <metadata>
    <nova:instance xmlns:nova="http://openstack.org/xmlns/libvirt/nova/1.0">
      <nova:package version="14.0.3-9.el7ost"/>
      <nova:name>wm-solr</nova:name>
      <nova:creationTime>2017-05-24 15:29:24</nova:creationTime>
      <nova:flavor name="m1.large">
        <nova:memory>8192</nova:memory>
        <nova:disk>80</nova:disk>
        <nova:swap>0</nova:swap>
        <nova:ephemeral>0</nova:ephemeral>
        <nova:vcpus>4</nova:vcpus>
      </nova:flavor>
      <nova:owner/>
      <nova:root type="image" uuid="a332ad63-8b38-4700-b818-b39fa69233a9"/>
    </nova:instance>
  </metadata>

This results in discover_libvirt_polling in ceilometer/compute/discovery throwing an AttributeError traceback when it tries to access:

  user_id = metadata_xml.find("./owner/user").attrib["uuid"]

This means that it will fail to poll any subsequent libvirt guests, which means the loss of many metrics.

Version-Release number of selected component (if applicable):

openstack-ceilometer-compute-9.0.3-1.el7ost.noarch

How reproducible:


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