根据官方文档，执行
$ source admin-openrc.sh
$ nova service-list
报错如下：
ada-ubuntu@ada-ubuntu:~$ nova service-list
+----+------------------+------------+----------+---------+-------+------------+-----------------+
| Id | Binary | Host | Zone | Status | State | Updated_at | Disabled Reason |
+----+------------------+------------+----------+---------+-------+------------+-----------------+
| 3 | nova-cert | ada-ubuntu | internal | enabled | down | - | - |
| 4 | nova-consoleauth | ada-ubuntu | internal | enabled | down | - | - |
| 5 | nova-scheduler | ada-ubuntu | internal | enabled | down | - | - |
| 6 | nova-conductor | ada-ubuntu | internal | enabled | down | - | - |
+----+------------------+------------+----------+---------+-------+------------+-----------------+
可看出Host少了一个compute， State全为down
首先查看/nova-compute日志：
sudo vim /var/log/nova/nova-compute.log
显示：
2017-09-26 16:48:16.257 14024 ERROR nova (class_id, method_id), ConnectionError)
2017-09-26 16:48:16.257 14024 ERROR nova AccessRefused: (0, 0): (403) ACCESS_REFUSED - Login was refused using authentication mechanism AMQPLAIN. For details see the broker logfile.
2017-09-26 16:48:16.257 14024 ERROR nova
然后查看rabbitmq日志：
sudo vim /var/log/rabbitmq/rabbit@ada-ubuntu.log
显示：
=INFO REPORT==== 26-Sep-2017::18:43:56 ===
accepting AMQP connection <0.7526.1> (10.0.0.31:34092 -> 10.0.0.11:5672)
=ERROR REPORT==== 26-Sep-2017::18:43:56 ===
closing AMQP connection <0.7523.1> (10.0.0.31:34090 -> 10.0.0.11:5672):
{handshake_error,starting,0,
{amqp_error,access_refused,
"AMQPLAIN login refused: user 'guest' can only connect via localhost",
'connection.start_ok'}}
解决方法：
修改配置文件/etc/rabbitmq/rabbitmq.config。如不存在，自己创建一个，在里面添加如下1行内容：[rabbit,[{loopback_users,[]}]}].
重启rabbitmq：
root@ada-ubuntu:/home/ada-ubuntu# service rabbitmq-server restart
发现问题仍未解决！
然后查看rabbitmq日志：
sudo vim /var/log/rabbitmq/rabbit@ada-ubuntu.log
显示：=INFO REPORT==== 26-Sep-2017::18:52:08 ===
accepting AMQP connection <0.217.0> (10.0.0.31:34132 -> 10.0.0.11:5672)
连接已建立，再往上看日志：
=ERROR REPORT==== 26-Sep-2017::18:52:05 ===
Error on AMQP connection <0.236.0> (10.0.0.31:34128 -> 10.0.0.11:5672, vhost: '/', user: 'guest', state: running), channel 0:
{amqp_error,connection_forced,
"broker forced connection closure with reason 'shutdown'",none}
接着重启所有compute services，问题解决！
root@ada-ubuntu:/home/ada-ubuntu# service nova-api restart
root@ada-ubuntu:/home/ada-ubuntu# service nova-cert restart
root@ada-ubuntu:/home/ada-ubuntu# service nova-consoleauth restart
root@ada-ubuntu:/home/ada-ubuntu# service nova-scheduler restart
root@ada-ubuntu:/home/ada-ubuntu# service nova-conductor restart
root@ada-ubuntu:/home/ada-ubuntu# service nova-novncproxy restart
重新执行指令如下：
ada-ubuntu@ada-ubuntu:~$ source admin-openrc.sh
ada-ubuntu@ada-ubuntu:~$ nova service-list
+----+------------------+------------+----------+---------+-------+----------------------------+-----------------+
| Id | Binary | Host | Zone | Status | State | Updated_at | Disabled Reason |
+----+------------------+------------+----------+---------+-------+----------------------------+-----------------+
| 3 | nova-cert | ada-ubuntu | internal | enabled | up | 2017-09-26T13:03:46.000000 | - |
| 4 | nova-consoleauth | ada-ubuntu | internal | enabled | up | 2017-09-26T13:03:48.000000 | - |
| 5 | nova-scheduler | ada-ubuntu | internal | enabled | up | 2017-09-26T13:03:46.000000 | - |
| 6 | nova-conductor | ada-ubuntu | internal | enabled | up | 2017-09-26T13:03:46.000000 | - |
| 7 | nova-compute | ada-ubuntu | nova | enabled | up | 2017-09-26T13:03:46.000000 | - |
+----+------------------+------------+----------+---------+-------+----------------------------+-----------------+