Open Stack

On 20/10/2020 11:02, Javier Pena wrote:
>
>     Hi guys.
>     I'm trying to deploy with "packstack --allinone" and
>     it always (tried ~5 times) fails with:
>     ...
>     ERROR : Error appeared during Puppet
>     run:A.B.C.D_compute.pp
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>     pymysql.err.OperationalError: (1040, 'Too many
>     connections')
>     You will find full trace in log
>     /var/tmp/packstack/20201018-183415-ik3ijyw7/manifests/172.24.154.202_compute.pp.log
>     Please check log file
>     /var/tmp/packstack/20201018-183415-ik3ijyw7/openstack-setup.log
>     for more information
>
>
>     If some expert might be interested then in
>     /var/tmp/packstack/20201018-183415-ik3ijyw7/manifests/172.24.154.202_compute.pp.log
>     ....
>     Notice:
>     /Stage[main]/Nova::Compute::Libvirt/Nova_config[DEFAULT/compute_driver]/ensure:
>     created
>     Notice:
>     /Stage[main]/Nova::Compute::Libvirt/Nova_config[vnc/server_listen]/ensure:
>     created
>     Notice:
>     /Stage[main]/Nova::Compute::Libvirt/Nova_config[libvirt/virt_type]/ensure:
>     created
>     Notice:
>     /Stage[main]/Nova::Compute::Libvirt/Nova_config[libvirt/cpu_mode]/ensure:
>     created
>     Notice:
>     /Stage[main]/Nova::Compute::Libvirt/Nova_config[libvirt/inject_password]/ensure:
>     created
>     Notice:
>     /Stage[main]/Nova::Compute::Libvirt/Nova_config[libvirt/inject_key]/ensure:
>     created
>     Notice:
>     /Stage[main]/Nova::Compute::Libvirt/Nova_config[libvirt/inject_partition]/ensure:
>     created
>     Notice:
>     /Stage[main]/Nova::Migration::Libvirt/Nova_config[libvirt/live_migration_uri]/ensure:
>     created
>     Notice:
>     /Stage[main]/Nova::Compute::Libvirt::Services/Service[libvirt]/ensure:
>     ensure changed 'stopped' to 'running'
>     Notice:
>     /Stage[main]/Neutron::Deps/Anchor[neutron::service::begin]:
>     Triggered 'refresh' from 2 events
>     Notice:
>     /Stage[main]/Nova::Deps/Anchor[nova::config::end]:
>     Triggered 'refresh' from 22 events
>     Notice:
>     /Stage[main]/Nova::Deps/Anchor[nova::service::begin]:
>     Triggered 'refresh' from 1 event
>     Notice:
>     /Stage[main]/Nova::Compute/Nova::Generic_service[compute]/Service[nova-compute]/ensure:
>     ensure changed 'stopped' to 'running'
>     Notice:
>     /Stage[main]/Nova::Deps/Anchor[nova::service::end]:
>     Triggered 'refresh' from 1 event
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>     An error has occurred:
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>     Traceback (most recent call last):
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py",
>     line 2262, in _wrap_pool_connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return fn()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 294, in unique_connection
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return _ConnectionFairy._checkout(self)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 751, in _checkout
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     fairy = _ConnectionRecord.checkout(pool)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 483, in checkout
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     rec = pool._do_get()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/impl.py",
>     line 138, in _do_get
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self._dec_overflow()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/util/langhelpers.py",
>     line 68, in __exit__
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     compat.reraise(exc_type, exc_value, exc_tb)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/util/compat.py",
>     line 129, in reraise
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     raise value
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/impl.py",
>     line 135, in _do_get
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return self._create_connection()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 299, in _create_connection
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return _ConnectionRecord(self)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 428, in __init__
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self.__connect(first_connect_check=True)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 630, in __connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     connection = pool._invoke_creator(self)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/strategies.py",
>     line 114, in connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return dialect.connect(*cargs, **cparams)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/default.py",
>     line 453, in connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return self.dbapi.connect(*cargs, **cparams)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/__init__.py",
>     line 94, in Connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return Connection(*args, **kwargs)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/connections.py",
>     line 325, in __init__
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self.connect()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/connections.py",
>     line 599, in connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self._request_authentication()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/connections.py",
>     line 861, in _request_authentication
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     auth_packet = self._read_packet()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/connections.py",
>     line 684, in _read_packet
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     packet.check_error()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/protocol.py",
>     line 220, in check_error
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     err.raise_mysql_exception(self._data)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/err.py",
>     line 109, in raise_mysql_exception
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     raise errorclass(errno, errval)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>     pymysql.err.OperationalError: (1040, 'Too many
>     connections')
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>     The above exception was the direct cause of the
>     following exception:
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>     Traceback (most recent call last):
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/nova/cmd/manage.py",
>     line 2777, in main
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     ret = fn(*fn_args, **fn_kwargs)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/nova/cmd/manage.py",
>     line 1144, in discover_hosts
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     by_service)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/nova/objects/host_mapping.py",
>     line 256, in discover_hosts
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     cell_mappings = objects.CellMappingList.get_all(ctxt)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/oslo_versionedobjects/base.py",
>     line 184, in wrapper
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     result = fn(cls, context, *args, **kwargs)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/nova/objects/cell_mapping.py",
>     line 256, in get_all
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     db_mappings = cls._get_all_from_db(context)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/oslo_db/sqlalchemy/enginefacade.py",
>     line 1013, in wrapper
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     with self._transaction_scope(context):
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File "/usr/lib64/python3.6/contextlib.py", line 81, in
>     __enter__
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return next(self.gen)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/oslo_db/sqlalchemy/enginefacade.py",
>     line 1063, in _transaction_scope
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     context=context) as resource:
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File "/usr/lib64/python3.6/contextlib.py", line 81, in
>     __enter__
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return next(self.gen)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/oslo_db/sqlalchemy/enginefacade.py",
>     line 658, in _session
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     bind=self.connection, mode=self.mode)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/oslo_db/sqlalchemy/enginefacade.py",
>     line 418, in _create_session
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self._start()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/oslo_db/sqlalchemy/enginefacade.py",
>     line 510, in _start
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     engine_args, maker_args)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/oslo_db/sqlalchemy/enginefacade.py",
>     line 534, in _setup_for_connection
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     sql_connection=sql_connection, **engine_kwargs)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/debtcollector/renames.py",
>     line 43, in decorator
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return wrapped(*args, **kwargs)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/oslo_db/sqlalchemy/engines.py",
>     line 201, in create_engine
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     test_conn = _test_connection(engine, max_retries,
>     retry_interval)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/oslo_db/sqlalchemy/engines.py",
>     line 376, in _test_connection
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return engine.connect()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py",
>     line 2193, in connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return self._connection_cls(self, **kwargs)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py",
>     line 103, in __init__
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     else engine.raw_connection()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py",
>     line 2293, in raw_connection
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self.pool.unique_connection, _connection
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py",
>     line 2266, in _wrap_pool_connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     e, dialect, self
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py",
>     line 1534, in _handle_dbapi_exception_noconnection
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     util.raise_from_cause(newraise, exc_info)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/util/compat.py",
>     line 383, in raise_from_cause
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     reraise(type(exception), exception, tb=exc_tb,
>     cause=cause)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/util/compat.py",
>     line 128, in reraise
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     raise value.with_traceback(tb)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py",
>     line 2262, in _wrap_pool_connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return fn()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 294, in unique_connection
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return _ConnectionFairy._checkout(self)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 751, in _checkout
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     fairy = _ConnectionRecord.checkout(pool)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 483, in checkout
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     rec = pool._do_get()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/impl.py",
>     line 138, in _do_get
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self._dec_overflow()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/util/langhelpers.py",
>     line 68, in __exit__
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     compat.reraise(exc_type, exc_value, exc_tb)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/util/compat.py",
>     line 129, in reraise
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     raise value
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/impl.py",
>     line 135, in _do_get
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return self._create_connection()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 299, in _create_connection
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return _ConnectionRecord(self)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 428, in __init__
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self.__connect(first_connect_check=True)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/pool/base.py",
>     line 630, in __connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     connection = pool._invoke_creator(self)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/strategies.py",
>     line 114, in connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return dialect.connect(*cargs, **cparams)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/default.py",
>     line 453, in connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return self.dbapi.connect(*cargs, **cparams)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/__init__.py",
>     line 94, in Connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     return Connection(*args, **kwargs)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/connections.py",
>     line 325, in __init__
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self.connect()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/connections.py",
>     line 599, in connect
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     self._request_authentication()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/connections.py",
>     line 861, in _request_authentication
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     auth_packet = self._read_packet()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/connections.py",
>     line 684, in _read_packet
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     packet.check_error()
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/protocol.py",
>     line 220, in check_error
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     err.raise_mysql_exception(self._data)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:  
>     File
>     "/usr/lib/python3.6/site-packages/pymysql/err.py",
>     line 109, in raise_mysql_exception
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:    
>     raise errorclass(errno, errval)
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>     sqlalchemy.exc.OperationalError:
>     (pymysql.err.OperationalError) (1040, 'Too many
>     connections')
>     Notice:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]/returns:
>     (Background on this error at: http://sqlalche.me/e/e3q8)
>     Error:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]:
>     Failed to call refresh: 'nova-manage  cell_v2
>     discover_hosts' returned 255 instead of one of [0]
>     Error:
>     /Stage[main]/Nova::Cell_v2::Discover_hosts/Exec[nova-cell_v2-discover_hosts]:
>     'nova-manage  cell_v2 discover_hosts' returned 255
>     instead of one of [0]
>
> Hi,
>
> This might happen if you have a lot of CPUs in your
> machine, since Packstack will spawn by default 1 worker
> per CPU on every service. In some cases, that is too much
> for the default MariaDB open file parameters.
>
> Can you try adding "--service-workers=2" to your packstack
> command-line? Alternatively, you can set the
> CONFIG_SERVICE_WORKERS option in your answer file.
>
Yes! that seems to be the fix for my. Lots of cores in the
box is my case.

> Regards,
> Javier
>
>     Bit discouraging to fail at start but I trust you can
>     share some good advice.
>     I'm on Centos8 with ussuri.
>     Many thanks, L.
>
>