计算节点nova服务启动失败

在计算节点启动openstack-nova-compute服务的时候，服务无法正常启动，查看nova的日志发现如下报错：
2019-04-25 00:02:26.481 24682 ERROR nova Traceback (most recent call last):
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/bin/nova-compute”, line 10, in
2019-04-25 00:02:26.481 24682 ERROR nova sys.exit(main())
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/nova/cmd/compute.py”, line 57, in main
2019-04-25 00:02:26.481 24682 ERROR nova topic=compute_rpcapi.RPC_TOPIC)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/nova/service.py”, line 259, in create
2019-04-25 00:02:26.481 24682 ERROR nova periodic_interval_max=periodic_interval_max)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/nova/service.py”, line 130, in init
2019-04-25 00:02:26.481 24682 ERROR nova conductor_api.wait_until_ready(context.get_admin_context())
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/nova/conductor/api.py”, line 67, in wait_until_ready
2019-04-25 00:02:26.481 24682 ERROR nova timeout=timeout)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/nova/baserpc.py”, line 58, in ping
2019-04-25 00:02:26.481 24682 ERROR nova return cctxt.call(context, ‘ping’, arg=arg_p)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/rpc/client.py”, line 179, in call
2019-04-25 00:02:26.481 24682 ERROR nova retry=self.retry)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/transport.py”, line 133, in _send
2019-04-25 00:02:26.481 24682 ERROR nova retry=retry)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py”, line 584, in send
2019-04-25 00:02:26.481 24682 ERROR nova call_monitor_timeout, retry=retry)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py”, line 526, in _send
2019-04-25 00:02:26.481 24682 ERROR nova msg.update({’_reply_q’: self._get_reply_q()})
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py”, line 507, in _get_reply_q
2019-04-25 00:02:26.481 24682 ERROR nova conn = self._get_connection(rpc_common.PURPOSE_LISTEN)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py”, line 498, in _get_connection
2019-04-25 00:02:26.481 24682 ERROR nova purpose=purpose)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/common.py”, line 407, in init
2019-04-25 00:02:26.481 24682 ERROR nova self.connection = connection_pool.create(purpose)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/pool.py”, line 144, in create
2019-04-25 00:02:26.481 24682 ERROR nova return self.connection_cls(self.conf, self.url, purpose)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/impl_rabbit.py”, line 601, in init
2019-04-25 00:02:26.481 24682 ERROR nova self.ensure_connection()
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/impl_rabbit.py”, line 700, in ensure_connection
2019-04-25 00:02:26.481 24682 ERROR nova self.ensure(method=self.connection.connect)
2019-04-25 00:02:26.481 24682 ERROR nova File “/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/impl_rabbit.py”, line 811, in ensure
2019-04-25 00:02:26.481 24682 ERROR nova raise exceptions.MessageDeliveryFailure(msg)
2019-04-25 00:02:26.481 24682 ERROR nova MessageDeliveryFailure: Unable to connect to AMQP server on controller:5672 after None tries: (0, 0): (403) ACCESS_REFUSED - Login was refused using authentication mechanism AMQPLAIN. For details see the broker logfile.

此时在控制节点查看rabbitmq用户
rabbitmqctl list_users
Listing users
guest [administrator]

发现之前创建的openstack用户不见了。重新添加openstack用户：
#rabbitmqctl add_user openstack RABBIT_PASS

赋予权限
#rabbitmqctl set_permissions openstack “." ".” “.*”
Setting permissions for user “openstack” in vhost “/”

赋予openstackadministrator标签
Setting tags for user “openstack” to [administrator]

#systemctl restart rabbitmq-server.service

最后在计算节点重启服务
systemctl restart openstack-nova-compute.service
服务正常启动