Hello All,

    I am trying to launch a VM instance on Ocata Ubuntu 16.04 openstack environment but I am getting this error on dashboard.`enter code here`

    ****Error:-****Failed to perform requested operation on instance "VM 1", the instance has an error status: Please try again later [Error: No valid host was found. There are not enough hosts available.]

    After checking in nova-conductor.log, it gives the following error:-

    2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db     return connection._execute_clauseelement(self, multiparams, params)
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db   File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/base.py", line 1010, in _execute_clauseelement
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db     compiled_sql, distilled_params
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db   File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/base.py", line 1146, in _execute_context
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db     context)
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db   File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/base.py", line 1337, in _handle_dbapi_exception
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db     util.raise_from_cause(newraise, exc_info)
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db   File "/usr/lib/python2.7/dist-packages/sqlalchemy/util/compat.py", line 200, in raise_from_cause
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db     reraise(type(exception), exception, tb=exc_tb)
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db   File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/base.py", line 1139, in _execute_context
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db     context)
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db   File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/default.py", line 450, in do_execute
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db     cursor.execute(statement, parameters)
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db OperationalError: (sqlite3.OperationalError) database is locked [SQL: u'UPDATE services SET updated_at=?, report_count=?, last_seen_up=? WHERE services.id = ?'] [parameters: ('2017-07-28 16:17:02.395709', 10, '2017-07-28 16:17:02.395151', 3)]
2017-07-28 09:17:02.396 22067 ERROR nova.servicegroup.drivers.db
2017-07-28 09:17:12.579 22067 INFO nova.servicegroup.drivers.db [-] Recovered from being unable to report status.
2017-07-28 09:17:32.409 22065 ERROR nova.servicegroup.drivers.db [-] Unexpected error while reporting service status
2017-07-28 09:17:32.409 22065 ERROR nova.servicegroup.drivers.db Traceback (most recent call last):
2017-07-28 09:17:32.409 22065 ERROR nova.servicegroup.drivers.db   File "/usr/lib/python2.7/dist-packages/nova/servicegroup/drivers/db.py", line 87, in _report_state
2017-07-28 09:17:32.409 22065 ERROR nova.servicegroup.drivers.db     service.service_ref.save()
2017-07-28 09:17:32.409 22065 ERROR nova.servicegroup.drivers.db   File "/usr/lib/python2.7/dist-packages/oslo_versionedobjects/base.py", line 226, in wrapper
2017-07-28 09:17:32.409 22065 ERROR nova.servicegroup.drivers.db     return ...