Comment 4 for bug 1515032

It takes up to two minutes to restore a connection to the database. In the worst case scenario a test can fail before the connection is restored.

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2015-11-12 15:53:16.247 17115 TRACE nova.servicegroup.drivers.db dbapi_connection = rec.get_connection()
2015-11-12 15:53:16.247 17115 TRACE nova.servicegroup.drivers.db File "/usr/lib/python2.7/dist-packages/sqlalchemy/pool.py", line 525, in get_connection
2015-11-12 15:53:16.247 17115 TRACE nova.servicegroup.drivers.db self.connection = self.__connect()
2015-11-12 15:53:16.247 17115 TRACE nova.servicegroup.drivers.db File "/usr/lib/python2.7/dist-packages/sqlalchemy/pool.py", line 537, in __connect
2015-11-12 15:53:16.247 17115 TRACE nova.servicegroup.drivers.db connection = self.__pool._creator()
2015-11-12 15:53:16.247 17115 TRACE nova.servicegroup.drivers.db File "/usr/lib/python2.7/dist-packages/oslo_db/sqlalchemy/compat/handle_error.py", line 200, in connect
2015-11-12 15:53:16.247 17115 TRACE nova.servicegroup.drivers.db raise original_exception
2015-11-12 15:53:16.247 17115 TRACE nova.servicegroup.drivers.db DBConnectionError: (OperationalError) (2013, "Lost connection to MySQL server at 'reading initial communication packet', system error: 0") None None
2015-11-12 15:53:16.247 17115 TRACE nova.servicegroup.drivers.db
2015-11-12 15:53:26.872 17115 INFO nova.scheduler.host_manager [req-79360310-a2a9-4ada-bf84-e058145484f2 - - - - -] Successfully synced instances from host 'node-4.test.domain.local'.
2015-11-12 15:54:13.195 17115 ERROR nova.servicegroup.drivers.db [req-a3fd5579-559e-4eb7-b56b-364b246f5910 - - - - -] Recovered model server connection!
2015-11-12 15:55:13.181 17115 ERROR sqlalchemy.pool.QueuePool [req-a3fd5579-559e-4eb7-b56b-364b246f5910 - - - - -] Exception closing connection <_mysql.connection closed at 2ab4190>
2015-11-12 15:55:13.181 17115 TRACE sqlalchemy.pool.QueuePool Traceback (most recent call last):
2015-11-12 15:55:13.181 17115 TRACE sqlalchemy.pool.QueuePool File "/usr/lib/python2.7/dist-packages/sqlalchemy/pool.py", line 250, in _close_connection
2015-11-12 15:55:13.181 17115 TRACE sqlalchemy.pool.QueuePool self._dialect.do_close(connection)
2015-11-12 15:55:13.181 17115 TRACE sqlalchemy.pool.QueuePool File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/default.py", line 412, in do_close
2015-11-12 15:55:13.181 17115 TRACE sqlalchemy.pool.QueuePool dbapi_connection.close()
2015-11-12 15:55:13.181 17115 TRACE sqlalchemy.pool.QueuePool ProgrammingError: closing a closed connection
2015-11-12 15:55:13.181 17115 TRACE sqlalchemy.pool.QueuePool
2015-11-12 15:55:43.456 17115 INFO nova.scheduler.host_manager [req-9d41807c-6267-43e0-94a8-4988463b6561 - - - - -] Successfully synced instances from host 'node-4.test.domain.local'.