Comment 0 for bug 1913607

I'm hitting the following error on ussuri and prior. Worth noting, this is a package build for ubuntu.

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FAIL: cinder.tests.unit.volume.drivers.test_quobyte.QuobyteDriverTestCase.test_mount_quobyte_should_reraise_already_mounted_error
cinder.tests.unit.volume.drivers.test_quobyte.QuobyteDriverTestCase.test_mount_quobyte_should_reraise_already_mounted_error
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_StringException: pythonlogging:'': {{{
2021-01-27 18:46:39,044 INFO [keystonemiddleware.auth_token] Starting Keystone auth_token middleware
2021-01-27 18:46:39,047 WARNING [keystonemiddleware._common.config] The option "auth_url" is not known to keystonemiddleware
2021-01-27 18:46:39,047 WARNING [keystonemiddleware.auth_token] AuthToken middleware is set with keystone_authtoken.service_token_roles_required set to False. This is backwards compatible but deprecated behaviour. Please set this to True.
2021-01-27 18:46:39,050 WARNING [keystonemiddleware.auth_token] Configuring www_authenticate_uri to point to the public identity endpoint is required; clients may not be able to authenticate against an admin endpoint
2021-01-27 18:46:39,069 INFO [cinder.volume.drivers.quobyte] The NAS file operations will be run as non privileged user in secure mode. Please ensure your libvirtd settings have been configured accordingly (see section 'OpenStack' in the Quobyte Manual.
2021-01-27 18:46:39,070 INFO [cinder.volume.drivers.quobyte] Mounting volume: quobyte://quobyte-host/openstack-volumes ...
2021-01-27 18:46:39,071 INFO [cinder.volume.drivers.quobyte] Mounting volume: quobyte://quobyte-host/openstack-volumes succeeded
}}}

Traceback (most recent call last):
  File "/<<PKGBUILDDIR>>/cinder/tests/unit/volume/drivers/test_quobyte.py", line 463, in test_mount_quobyte_should_reraise_already_mounted_error
    ensure=False)
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 485, in assertRaises
    self.assertThat(our_callable, matcher)
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 496, in assertThat
    mismatch_error = self._matchHelper(matchee, matcher, message, verbose)
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 547, in _matchHelper
    mismatch = matcher.match(matchee)
  File "/usr/lib/python3/dist-packages/testtools/matchers/_exception.py", line 108, in match
    mismatch = self.exception_matcher.match(exc_info)
  File "/usr/lib/python3/dist-packages/testtools/matchers/_higherorder.py", line 62, in match
    mismatch = matcher.match(matchee)
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 475, in match
    reraise(*matchee)
  File "/usr/lib/python3/dist-packages/testtools/_compat3x.py", line 16, in reraise
    raise exc_obj.with_traceback(exc_tb)
  File "/usr/lib/python3/dist-packages/testtools/matchers/_exception.py", line 101, in match
    result = matchee()
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 1049, in __call__
    return self._callable_object(*self._args, **self._kwargs)
  File "/<<PKGBUILDDIR>>/cinder/volume/drivers/quobyte.py", line 699, in _mount_quobyte
    self._validate_volume(mount_path)
  File "/<<PKGBUILDDIR>>/cinder/volume/drivers/quobyte.py", line 705, in _validate_volume
    partitions = psutil.disk_partitions(all=True)
  File "/usr/lib/python3/dist-packages/psutil/__init__.py", line 2095, in disk_partitions
    return _psplatform.disk_partitions(all)
  File "/usr/lib/python3/dist-packages/psutil/_pslinux.py", line 1168, in disk_partitions
    partitions = cext.disk_partitions(mtab_path)
FileNotFoundError: [Errno 2] No such file or directory: '/etc/mtab'

This is similiar to: https://bugs.launchpad.net/cinder/+bug/1675861