fails with start neutron-openvswitch-agent returned 6 问题解决

运行出现的问题：

Welcome to the Packstack setup utility

The installation log file is available at: /var/tmp/packstack/20160802-150952-n_grQs/openstack-setup.log

Installing:
Clean Up                                             [ DONE ]
Discovering ip protocol version                      [ DONE ]
Setting up ssh keys                                  [ DONE ]
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Fixing Keystone LDAP config parameters to be undef if empty[ DONE ]
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Checking if the Cinder server has a cinder-volumes vg[ DONE ]
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Creating ssh keys for Nova migration                 [ DONE ]
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Checking if NetworkManager is enabled and running    [ DONE ]
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Preparing Puppet manifests                           [ DONE ]
Copying Puppet modules and manifests                 [ DONE ]
Applying 172.18.31.17_controller.pp
172.18.31.17_controller.pp:                          [ DONE ]         
Applying 172.18.31.17_network.pp
172.18.31.17_network.pp:                          [ ERROR ]        
Applying Puppet manifests                         [ ERROR ]

ERROR : Error appeared during Puppet run: 172.18.31.17_network.pp
Error: Could not start Service[neutron-ovs-agent-service]: Execution of '/usr/bin/systemctl start neutron-openvswitch-age
nt' returned 6: Failed to start neutron-openvswitch-agent.service: Unit neutron-openvswitch-agent.service failed to load: No such file or directory.You will find full trace in log /var/tmp/packstack/20160802-150952-n_grQs/manifests/172.18.31.17_network.pp.log
Please check log file /var/tmp/packstack/20160802-150952-n_grQs/openstack-setup.log for more information
Additional information:
 * A new answerfile was created in: /root/packstack-answers-20160802-150953.txt
 * Time synchronization installation was skipped. Please note that unsynchronized time on server instances might be probl
em for some OpenStack components. * File /root/keystonerc_admin has been created on OpenStack client host 172.18.31.17. To use the command line tools you 
need to source the file. * To access the OpenStack Dashboard browse to http://172.18.31.17/dashboard .
Please, find your login credentials stored in the keystonerc_admin in your home directory.
 * To use Nagios, browse to http://172.18.31.17/nagios username: nagiosadmin, password: da27eff608e84b7b

解决方法原帖：

https://ask.openstack.org/en/question/56927/reinstallation-fails-with-start-neutron-openvswitch-agent-returned-6/

下面粘的是里面的一个回答，亲测可用

Attempt follow https://scottlinux.com/2014/12/08/how…
Make sure neutron database && keystone database are in good shape
I would try create under /lib/systemd/system file neutron-openvswitch-agent.service :-

[Unit]
Description=OpenStack Neutron Open vSwitch Agent
After=syslog.target network.target

[Service]
Type=simple
User=neutron
ExecStart=/usr/bin/neutron-openvswitch-agent --config-file /usr/share/neutron/neutron-dist.conf --config-file /etc/neutron/neutron.conf --config-file /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini --log-file /var/log/neutron/openvswitch-agent.log
PrivateTmp=true
KillMode=process

[Install]
WantedBy=multi-user.target

以上这个文件并不是和回答里面的一模一样，但不要紧，继续往下

[root@junodocker system]# pwd
/etc/systemd/system
[root@junodocker system]# ls -l multi-user.target.wants | grep neutron-openvswitch
lrwxrwxrwx. 1 root root 57 Dec 20 09:22 neutron-openvswitch-agent.service -> /usr/lib/systemd/system/neutron-openvswitch-agent.service

[root@junodocker system]# pwd
/usr/lib/systemd/system
[root@junodocker system]# ls -l | grep neutron-openvswitch
-rw-r--r--. 1 root root  454 Dec  5 16:09 neutron-openvswitch-agent.service
[root@junodocker system]# cat neutron-openvswitch-agent.service
[Unit]
Description=OpenStack Neutron Open vSwitch Agent
After=syslog.target network.target

[Service]
Type=simple
User=neutron
ExecStart=/usr/bin/neutron-openvswitch-agent --config-file /usr/share/neutron/neutron-dist.conf --config-file /etc/neutron/neutron.conf --config-file /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini --log-file /var/log/neutron/openvswitch-agent.log
PrivateTmp=true
KillMode=process

[Install]
WantedBy=multi-user.target


#  systemctl daemon-reload
#  systemctl enable neutron-openvswitch-agent.service
#  systemctl start  neutron-openvswitch-agent.service

后三条命令执行完之后问题就解决了