Comment 0 for bug 812548

I'm attempting to demo/use LXC backend for nova in EC2, all on a single system.
When doing so, I get the following trace:

2011-07-18 20:31:20,962 DEBUG nova.utils [-] Running cmd (subprocess): sudo vconfig add None 100 from (pid=20109) execute /usr/lib/pymodules/python2.7/nova/utils.py:143
2011-07-18 20:31:20,994 DEBUG nova.utils [-] Result was 3 from (pid=20109) execute /usr/lib/pymodules/python2.7/nova/utils.py:161
2011-07-18 20:31:20,995 ERROR nova.exception [-] Uncaught exception
(nova.exception): TRACE: Traceback (most recent call last):
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.7/nova/exception.py", line 87, in _wrap
(nova.exception): TRACE: return f(*args, **kw)
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.7/nova/compute/manager.py", line 334, in run_instance
(nova.exception): TRACE: self._run_instance(context, instance_id, **kwargs)
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.7/nova/compute/manager.py", line 297, in _run_instance
(nova.exception): TRACE: instance_id)
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/manager.py", line 827, in setup_compute_network
(nova.exception): TRACE: network['bridge_interface'])
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/linux_net.py", line 456, in ensure_vlan_bridge
(nova.exception): TRACE: interface = ensure_vlan(vlan_num, bridge_interface)
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.7/nova/utils.py", line 613, in inner
(nova.exception): TRACE: retval = f(*args, **kwargs)
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/linux_net.py", line 467, in ensure_vlan
(nova.exception): TRACE: _execute('sudo', 'vconfig', 'add', bridge_interface, vlan_num)
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/linux_net.py", line 689, in _execute
(nova.exception): TRACE: return utils.execute(*cmd, **kwargs)
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.7/nova/utils.py", line 169, in execute
(nova.exception): TRACE: cmd=' '.join(cmd))
(nova.exception): TRACE: ProcessExecutionError: Unexpected error while running command.
(nova.exception): TRACE: Command: sudo vconfig add None 100
(nova.exception): TRACE: Exit code: 3
(nova.exception): TRACE: Stdout: ''
(nova.exception): TRACE: Stderr: 'ERROR: trying to add VLAN #100 to IF -:None:- error: No such device\n'

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: nova-network 2011.3~d3~20110708.1251-0ubuntu1
ProcVersionSignature: User Name 3.0.0-5.6-virtual 3.0.0-rc7
Uname: Linux 3.0.0-5-virtual x86_64
Architecture: amd64
Date: Mon Jul 18 20:45:23 2011
PackageArchitecture: all
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: nova
UpgradeStatus: No upgrade log present (probably fresh install)