安装OpenStack时，同步keystone数据库报错 keystone DBConnectionError: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on 'controller' ([Errno 111] Connection refused)")

执行命令 su -s /bin/sh -c "keystone-manage db_sync" keystone 时一直执行失败，查看/var/log/keystone/keystone.log找到报错如下

2021-09-27 09:05:18.381 185184 ERROR keystone Traceback (most recent call last):
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/bin/keystone-manage", line 10, in <module>
2021-09-27 09:05:18.381 185184 ERROR keystone sys.exit(main())
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/keystone/cmd/manage.py", line 44, in main
2021-09-27 09:05:18.381 185184 ERROR keystone cli.main(argv=sys.argv, config_files=config_files)
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/keystone/cmd/cli.py", line 1312, in main
2021-09-27 09:05:18.381 185184 ERROR keystone CONF.command.cmd_class.main()
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/keystone/cmd/cli.py", line 467, in main
2021-09-27 09:05:18.381 185184 ERROR keystone CONF.command.version)
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/keystone/common/sql/upgrades.py", line 251, in offline_sync_database_t o_version
2021-09-27 09:05:18.381 185184 ERROR keystone expand_schema()
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/keystone/common/sql/upgrades.py", line 271, in expand_schema
2021-09-27 09:05:18.381 185184 ERROR keystone _sync_common_repo(version=None)
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/keystone/common/sql/upgrades.py", line 167, in _sync_common_repo
2021-09-27 09:05:18.381 185184 ERROR keystone with sql.session_for_write() as session:
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
2021-09-27 09:05:18.381 185184 ERROR keystone return self.gen.next()
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/oslo_db/sqlalchemy/enginefacade.py", line 944, in _transaction_scope
2021-09-27 09:05:18.381 185184 ERROR keystone allow_async=self._allow_async) as resource:
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
2021-09-27 09:05:18.381 185184 ERROR keystone return self.gen.next()
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/oslo_db/sqlalchemy/enginefacade.py", line 558, in _session
2021-09-27 09:05:18.381 185184 ERROR keystone bind=self.connection, mode=self.mode)
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/oslo_db/sqlalchemy/enginefacade.py", line 317, in _create_session
2021-09-27 09:05:18.381 185184 ERROR keystone self._start()
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/oslo_db/sqlalchemy/enginefacade.py", line 403, in _start
2021-09-27 09:05:18.381 185184 ERROR keystone engine_args, maker_args)
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/oslo_db/sqlalchemy/enginefacade.py", line 427, in _setup_for_connectio n
2021-09-27 09:05:18.381 185184 ERROR keystone sql_connection=sql_connection, **engine_kwargs)
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/oslo_db/sqlalchemy/engines.py", line 155, in create_engine
2021-09-27 09:05:18.381 185184 ERROR keystone test_conn = _test_connection(engine, max_retries, retry_interval)
2021-09-27 09:05:18.381 185184 ERROR keystone File "/usr/lib/python2.7/site-packages/oslo_db/sqlalchemy/engines.py", line 339, in _test_connection
2021-09-27 09:05:18.381 185184 ERROR keystone six.reraise(type(de_ref), de_ref)
2021-09-27 09:05:18.381 185184 ERROR keystone File "<string>", line 2, in reraise
2021-09-27 09:05:18.381 185184 ERROR keystone DBConnectionError: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on 'controller' ([Errno 111] Connection refused)")
2021-09-27 09:05:18.381 185184 ERROR keystone
2021-09-27 10:09:09.147 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 10 attempts left.
2021-09-27 10:09:19.158 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 9 attempts left.
2021-09-27 10:09:29.169 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 8 attempts left.
2021-09-27 10:09:39.181 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 7 attempts left.
2021-09-27 10:09:49.193 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 6 attempts left.
2021-09-27 10:09:59.204 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 5 attempts left.
2021-09-27 10:10:09.216 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 4 attempts left.
2021-09-27 10:10:19.228 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 3 attempts left.
2021-09-27 10:10:29.240 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 2 attempts left.
2021-09-27 10:10:39.251 165810 WARNING oslo_db.sqlalchemy.engines [-] SQL connection failed. 1 attempts left.
2021-09-27 10:10:49.255 165810 CRITICAL keystone [-] DBConnectionError: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on 'controller' ([Errno 111] Connection refused)")