I have an Openstack Juno Network installed containing a controller, network and 5 compute nodes all running on Ubuntu. I want to add one more compute node on a Centos 7. But I'm getting authentication error. So I wanted to know if there is any incompatibilities with compute and networking services running on the 2 different Linux distros. Also there are some config files missing in the Centos installation such as api_paste.ini inthe Neutron and nova_compute.conf for Nova.

Please find attached error form the nova-compute.log from the Centos compute node,

2015-04-21 15:16:46.726 1005 ERROR nova.compute.manager [-] [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484] An error occurred while refreshing the network cache.
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484] Traceback (most recent call last):
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]   File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 5348, in _heal_instance_info_cache
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]     self._get_instance_nw_info(context, instance, use_slave=True)
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]   File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 1234, in _get_instance_nw_info
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]     instance)
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]   File "/usr/lib/python2.7/site-packages/nova/network/neutronv2/api.py", line 598, in get_instance_nw_info
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]     port_ids)
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]   File "/usr/lib/python2.7/site-packages/nova/network/neutronv2/api.py", line 612, in _get_instance_nw_info
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]     port_ids)
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]   File "/usr/lib/python2.7/site-packages/nova/network/neutronv2/api.py", line 1356, in _build_network_info_model
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]     data = client.list_ports(**search_opts)
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]   File "/usr/lib/python2.7/site-packages/nova/network/neutronv2/__init__.py", line 84, in wrapper
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]     ret = obj(*args, **kwargs)
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]   File "/usr/lib/python2.7/site-packages/neutronclient/v2_0/client.py", line 98, in with_params
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]     ret = self.function(instance, *args, **kwargs)
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]   File "/usr/lib/python2.7/site-packages/neutronclient/v2_0/client.py", line 312, in list_ports
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]     **_params)
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager [instance: 95a1aaa2-fadc-40a5-803a-98bfa58ee484]   File "/usr/lib/python2.7/site-packages/nova/network/neutronv2/__init__.py", line 84, in wrapper
2015-04-21 15:16:46.726 1005 TRACE nova.compute.manager ...