The real error is:
2012-09-05 11:23:00 ERROR nova.rpc.amqp
[req-3e174011-b6cd-40ba-9066-5018df246c3e None None] Exception during
message handling
2012-09-05 11:23:00 TRACE nova.rpc.amqp Traceback (most recent call
last):
2012-09-05 11:23:00 TRACE nova.rpc.amqp File
"/usr/lib/python2.7/dist-packages/nova/rpc/amqp.py", line 253, in
_process_data
2012-09-05 11:23:00 TRACE nova.rpc.amqp rval =
node_func(context=ctxt, **node_args)
2012-09-05 11:23:00 TRACE nova.rpc.amqp File
"/usr/lib/python2.7/dist-packages/nova/network/manager.py", line 257,
in wrapped
2012-09-05 11:23:00 TRACE nova.rpc.amqp return func(self,
context, *args, **kwargs)
2012-09-05 11:23:00 TRACE nova.rpc.amqp File
"/usr/lib/python2.7/dist-packages/nova/network/manager.py", line 949,
in get_instance_nw_info
2012-09-05 11:23:00 TRACE nova.rpc.amqp network =
self._get_network_by_id(context, vif['network_id'])
2012-09-05 11:23:00 TRACE nova.rpc.amqp File
"/usr/lib/python2.7/dist-packages/nova/network/manager.py", line
1722, in _get_network_by_id
2012-09-05 11:23:00 TRACE nova.rpc.amqp network_id)
2012-09-05 11:23:00 TRACE nova.rpc.amqp File
"/usr/lib/python2.7/dist-packages/nova/network/manager.py", line
1543, in _get_network_by_id
2012-09-05 11:23:00 TRACE nova.rpc.amqp return
self.db.network_get(context, network_id)
2012-09-05 11:23:00 TRACE nova.rpc.amqp File
"/usr/lib/python2.7/dist-packages/nova/db/api.py", line 755, in
network_get
2012-09-05 11:23:00 TRACE nova.rpc.amqp return
IMPL.network_get(context, network_id)
2012-09-05 11:23:00 TRACE nova.rpc.amqp File
"/usr/lib/python2.7/dist-packages/nova/db/sqlalchemy/api.py", line
120, in wrapper
2012-09-05 11:23:00 TRACE nova.rpc.amqp return f(*args, **kwargs)
2012-09-05 11:23:00 TRACE nova.rpc.amqp File
"/usr/lib/python2.7/dist-packages/nova/db/sqlalchemy/api.py", line
1935, in network_get
2012-09-05 11:23:00 TRACE nova.rpc.amqp raise
exception.NetworkNotFound(network_id=network_id)
2012-09-05 11:23:00 TRACE nova.rpc.amqp NetworkNotFound: Network 1
could not be found.