From provided log, I saw below errors.
I will try to reproduce it in my setup and check further.

{"log":"2019-07-19 05:17:45.335 1 ERROR oslo.messaging._drivers.impl_rabbit [-] [c4616b8e-1973-4934-abcd-edbccab40c7d] AMQP server on rabbitmq.openstack.svc.cluster.local:5672 is unreachable: [Errno 104] Connection reset by peer. Trying again in 1 seconds.: error: [Errno 104] Connection reset by peer\n","stream":"stdout","time":"2019-07-19T05:17:45.336051349Z"}
{"log":"2019-07-19 05:17:51.061 1 ERROR oslo_db.sqlalchemy.engines [req-c3320e24-d192-4e3e-b87d-f65c2ea1a13e - - - - -] Database connection was found disconnected; reconnecting: DBConnectionError: (pymysql.err.OperationalError) (2013, 'Lost connection to MySQL server during query') [SQL: u'SELECT 1'] (Background on this error at: http://sqlalche.me/e/e3q8)\n","stream":"stdout","time":"2019-07-19T05:17:51.064104242Z"}

{"log":"2019-07-19 05:17:45.427 1 ERROR oslo.messaging._drivers.impl_rabbit [-] [9b5b205e-f138-4471-9ebc-858358c7baef] AMQP server on rabbitmq.openstack.svc.cluster.local:5672 is unreachable: Basic.cancel: (0) 3. Trying again in 1 seconds.: ConsumerCancelled: Basic.cancel: (0) 3\n","stream":"stdout","time":"2019-07-19T05:17:45.428226962Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines [req-7c6bf1f1-4670-47df-8333-063e51a59285 - - - - -] Database connection was found disconnected; reconnecting: DBConnectionError: (pymysql.err.OperationalError) (2013, 'Lost connection to MySQL server during query') [SQL: u'SELECT 1'] (Background on this error at: http://sqlalche.me/e/e3q8)\n","stream":"stdout","time":"2019-07-19T05:17:45.6008754Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines Traceback (most recent call last):\n","stream":"stdout","time":"2019-07-19T05:17:45.60089745Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines   File \"/var/lib/openstack/lib/python2.7/site-packages/oslo_db/sqlalchemy/engines.py\", line 73, in _connect_ping_listener\n","stream":"stdout","time":"2019-07-19T05:17:45.600901396Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines     connection.scalar(select([1]))\n","stream":"stdout","time":"2019-07-19T05:17:45.600904434Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines   File \"/var/lib/openstack/lib/python2.7/site-packages/sqlalchemy/engine/base.py\", line 912, in scalar\n","stream":"stdout","time":"2019-07-19T05:17:45.60090709Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines     return self.execute(object_, *multiparams, **params).scalar()\n","stream":"stdout","time":"2019-07-19T05:17:45.600911245Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines   File \"/var/lib/openstack/lib/python2.7/site-packages/sqlalchemy/engine/base.py\", line 980, in execute\n","stream":"stdout","time":"2019-07-19T05:17:45.600913757Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines     return meth(self, multiparams, params)\n","stream":"stdout","time":"2019-07-19T05:17:45.600916528Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines   File \"/var/lib/openstack/lib/python2.7/site-packages/sqlalchemy/sql/elements.py\", line 273, in _execute_on_connection\n","stream":"stdout","time":"2019-07-19T05:17:45.600926595Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines     return connection._execute_clauseelement(self, multiparams, params)\n","stream":"stdout","time":"2019-07-19T05:17:45.600929445Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines   File \"/var/lib/openstack/lib/python2.7/site-packages/sqlalchemy/engine/base.py\", line 1099, in _execute_clauseelement\n","stream":"stdout","time":"2019-07-19T05:17:45.600931858Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines     distilled_params,\n","stream":"stdout","time":"2019-07-19T05:17:45.600934417Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines   File \"/var/lib/openstack/lib/python2.7/site-packages/sqlalchemy/engine/base.py\", line 1240, in _execute_context\n","stream":"stdout","time":"2019-07-19T05:17:45.600936884Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines     e, statement, parameters, cursor, context\n","stream":"stdout","time":"2019-07-19T05:17:45.600940242Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines   File \"/var/lib/openstack/lib/python2.7/site-packages/sqlalchemy/engine/base.py\", line 1456, in _handle_dbapi_exception\n","stream":"stdout","time":"2019-07-19T05:17:45.600942581Z"}
{"log":"2019-07-19 05:17:45.598 1 ERROR oslo_db.sqlalchemy.engines     util.raise_from_cause(newraise, exc_info)\n","stream":"stdout","time":"2019-07-19T05:17:45.600945278Z"}