The nova-network wasn't started.

[guanxiaohua2k6]

After I installed nova, I confirmed the status of service nova-network with the following command, and found nova-network wasn't started.

$ status nova-network
nova-network stop/waiting

BTW, there are error messages in /etc/nova/nova-network.

2011-11-07 10:44:37,499 CRITICAL nova [-] Unexpected error while running command.
Command: sudo iptables-save -t filter
Exit code: 1
Stdout: ''
Stderr: 'sudo: iptables-save: command not found\n'
(nova): TRACE: Traceback (most recent call last):
(nova): TRACE: File "/usr/bin/nova-network", line 49, in
(nova): TRACE: service.wait()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/service.py", line 357, in wait
(nova): TRACE: _launcher.wait()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/service.py", line 107, in wait
(nova): TRACE: service.wait()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/eventlet/greenthread.py", line 166, in wait
(nova): TRACE: return self._exit_event.wait()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/eventlet/event.py", line 116, in wait
(nova): TRACE: return hubs.get_hub().switch()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/eventlet/hubs/hub.py", line 177, in switch
(nova): TRACE: return self.greenlet.switch()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/eventlet/greenthread.py", line 192, in main
(nova): TRACE: result = function(_args, *_kwargs)
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/service.py", line 77, in run_server
(nova): TRACE: server.start()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/service.py", line 137, in start
(nova): TRACE: self.manager.init_host()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/network/manager.py", line 1002, in init_host
(nova): TRACE: self.driver.init_host()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/network/linux_net.py", line 404, in init_host
(nova): TRACE: iptables_manager.apply()
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/utils.py", line 685, in inner
(nova): TRACE: retval = f(_args, *_kwargs)
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/network/linux_net.py", line 312, in apply
(nova): TRACE: attempts=5)
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/network/linux_net.py", line 735, in _execute
(nova): TRACE: return utils.execute(_cmd, *_kwargs)
(nova): TRACE: File "/usr/lib/python2.7/dist-packages/nova/utils.py", line 188, in execute
(nova): TRACE: cmd=' '.join(cmd))
(nova): TRACE: ProcessExecutionError: Unexpected error while running command.
(nova): TRACE: Command: sudo iptables-save -t filter
(nova): TRACE: Exit code: 1
(nova): TRACE: Stdout: ''
(nova): TRACE: Stderr: 'sudo: iptables-save: command not found\n'

[guanxiaohua2k6]

The reason is that package iptables wasn't installed when installing nova-network.

The issue is fixed in the following commit.
12330f1
ccb675e