I built my small cloud development ambient (just 1 controller and 1 compute node) using DevStack and whenever I try to rejoin-stack I get theese errors cycling appearing on my n-api screen:

    Traceback (most recent call last):
      File "/usr/local/lib/python2.7/dist-packages/eventlet/hubs/hub.py", line 346, in fire_timers
        timer()
      File "/usr/local/lib/python2.7/dist-packages/eventlet/hubs/timer.py", line 56, in __call__
        cb(*args, **kw)
      File "/usr/local/lib/python2.7/dist-packages/eventlet/greenthread.py", line 194, in main
        result = function(*args, **kwargs)
      File "/opt/stack/nova/nova/openstack/common/service.py", line 448, in run_service
        service.start()
      File "/opt/stack/nova/nova/service.py", line 354, in start
        self.manager.init_host()
      File "/opt/stack/nova/nova/api/manager.py", line 39, in init_host
        self.network_driver.metadata_accept()
      File "/opt/stack/nova/nova/network/linux_net.py", line 653, in metadata_accept
        iptables_manager.apply()
      File "/opt/stack/nova/nova/network/linux_net.py", line 421, in apply
        self._apply()
      File "/opt/stack/nova/nova/openstack/common/lockutils.py", line 248, in inner
        return f(*args, **kwargs)
      File "/opt/stack/nova/nova/network/linux_net.py", line 441, in _apply
        attempts=5)
      File "/opt/stack/nova/nova/network/linux_net.py", line 1190, in _execute
        return utils.execute(*cmd, **kwargs)
      File "/opt/stack/nova/nova/utils.py", line 174, in execute
        return processutils.execute(*cmd, **kwargs)
      File "/opt/stack/nova/nova/openstack/common/processutils.py", line 178, in execute
        cmd=' '.join(cmd))
    ProcessExecutionError: Unexpected error while running command.
    Command: sudo nova-rootwrap /etc/nova/rootwrap.conf iptables-save -c
    Exit code: 1
    Stdout: ''
    Stderr: 'Traceback (most recent call last):\n  File "/usr/bin/nova-rootwrap", line 59, in <module>\n    from nova.rootwrap import wrapper\nImportError: No module named rootwrap\n'
    2013-12-06 10:28:54.175 ERROR nova.openstack.common.threadgroup [-] Unexpected error while running command.
    Command: sudo nova-rootwrap /etc/nova/rootwrap.conf iptables-save -c
    Exit code: 1
    Stdout: ''
    Stderr: 'Traceback (most recent call last):\n  File "/usr/bin/nova-rootwrap", line 59, in <module>\n    from nova.rootwrap import wrapper\nImportError: No module named rootwrap\n'
    2013-12-06 10:28:54.175 TRACE nova.openstack.common.threadgroup Traceback (most recent call last):
    2013-12-06 10:28:54.175 TRACE nova.openstack.common.threadgroup   File "/opt/stack/nova/nova/openstack/common/threadgroup.py", line 117, in wait
    2013-12-06 10:28:54.175 TRACE nova.openstack.common.threadgroup     x.wait()
    2013-12-06 10:28:54.175 TRACE nova.openstack.common.threadgroup   File "/opt/stack/nova/nova/openstack/common/threadgroup.py", line 49, in wait
    2013-12-06 10:28:54.175 TRACE nova.openstack.common.threadgroup     return self.thread.wait()
    2013-12-06 10:28:54.175 TRACE nova.openstack.common.threadgroup   File "/usr/local/lib/python2.7/dist-packages/eventlet/greenthread.py", line 168, in wait
    2013-12-06 10:28:54.175 TRACE nova.openstack.common.threadgroup     return self._exit_event.wait()
    2013-12-06 10:28:54.175 TRACE nova.openstack.common.threadgroup   File "/usr/local/lib/python2.7/dist-packages/eventlet/event.py", line 116, in wait
    2013-12-06 10:28:54.175 TRACE nova.openstack.common ...