in juno(ubuntu 14.04), nova-compute cannot make vm due to keystone auth failure.

in my nova-compute.log :

REQ: curl -i http://controller:35357/v2.0/tokens -X POST -H "User-Agent: python-neutronclient" -d '{"auth": {"tenantName": "service", "passwordCredentials": {"username": "neutron", "password": "REDACTED"}}}'
 http_log_req /usr/lib/python2.7/dist-packages/neutronclient/common/utils.py:138
2014-10-24 11:46:50.444 1845 DEBUG nova.openstack.common.lockutils [-] Releasing semaphore "refresh_cache-6bc711b4-5e69-418a-9a98-3ac7f18d44ec" lock /usr/lib/python2.7/dist-packages/nova/openstack/common/lockutils.py:238

2014-10-24 11:46:50.445 1845 ERROR nova.compute.manager [-] [instance: 6bc711b4-5e69-418a-9a98-3ac7f18d44ec] An error occurred while refreshing the network cache.

2014-10-24 11:46:50.445 1845 TRACE nova.compute.manager [instance: 6bc711b4-5e69-418a-9a98-3ac7f18d44ec] Traceback (most recent call last):
...
2014-10-24 11:46:50.445 1845 TRACE nova.compute.manager [instance: 6bc711b4-5e69-418a-9a98-3ac7f18d44ec] **AttributeError: 'HTTPClient' object has no attribute 'connections'**

at this time, keystone-all.log shows something wrong as follow:

root@controller:~/work# tail -f /var/log/keystone/keystone-all.log

2014-10-24 11:45:32.359 2100 DEBUG keystone.middleware.core [-] **Auth token not in the request header. Will not build auth context**. process_request /usr/lib/python2.7/dist-packages/keystone/middleware/core.py:270
2014-10-24 11:45:33.426 2100 DEBUG keystone.common.wsgi [-] arg_dict: {} __call__ /usr/lib/python2.7/dist-packages/keystone/common/wsgi.py:191

plz tell me how to go further... I cannot catch up what makes this problem. thanks in advance.