tempest failure

tempest_failure.txt

==============================
Failed 1 tests - output below:
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tempest.api.compute.servers.test_disk_config.ServerDiskConfigTestJSON.test_rebuild_server_with_auto_disk_config[gate]
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Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):
      File "tempest/api/compute/servers/test_disk_config.py", line 73, in test_rebuild_server_with_auto_disk_config
        self.client.wait_for_server_status(server['id'], 'ACTIVE')
      File "tempest/services/compute/json/servers_client.py", line 178, in wait_for_server_status
        ready_wait=ready_wait)
      File "tempest/common/waiters.py", line 73, in wait_for_server_status
        server_id=server_id)
    BuildErrorException: Server b470fbe3-de07-45db-b1da-fb5ae4cfa24b failed to build and is in ERROR status
    Details: {u'code': 500, u'message': u"\n--\nFailed to mount filesystem: Unexpected error while running command.\nCommand: sudo nova-rootwrap /etc/nova/rootwrap.conf mount /dev/nbd9 /opt/stack/data/nova/instances/b470fbe3-de07-45db-b1da-fb5ae4cfa24b/rootfs\nExit code: 32\nStdout: u''\nStderr: u'moun", u'created': u'2015-01-07T18:24:13Z'}
    Traceback (most recent call last):
    _StringException: Empty attachments:
      stderr
      stdout
    
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Totals
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Ran: 171 tests in 259.6770 sec.
 - Passed: 142
 - Skipped: 28
 - Failed: 1
Sum of execute time for each test: 460.4542 sec.