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Exercise 3.2 step 7d - script to join second hypervisor

Upon executing script - ./tools/discover_hosts.sh I am facing the following error:
ubuntu@compute-node:~/devstack$ ./tools/discover_hosts.sh
An error has occurred:
Traceback (most recent call last):
File "/opt/stack/nova/nova/cmd/manage.py", line 1923, in main
ret = fn(*fn_args, **fn_kwargs)
File "/opt/stack/nova/nova/cmd/manage.py", line 1631, in discover_hosts
File "/opt/stack/nova/nova/objects/host_mapping.py", line 240, in discover_hosts
cell_mappings = objects.CellMappingList.get_all(ctxt)
File "/usr/local/lib/python2.7/dist-packages/oslo_versionedobjects/base.py", line 184, inwrapper
result = fn(cls, context, *args, **kwargs)
File "/opt/stack/nova/nova/objects/cell_mapping.py", line 137, in get_all
db_mappings = cls._get_all_from_db(context)
File "/usr/local/lib/python2.7/dist-packages/oslo_db/sqlalchemy/enginefacade.py", line 980, in wrapper
with self._transaction_scope(context):
File "/usr/lib/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/local/lib/python2.7/dist-packages/oslo_db/sqlalchemy/enginefacade.py", line 1030, in _transaction_scope
context=context) as resource:
File "/usr/lib/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/local/lib/python2.7/dist-packages/oslo_db/sqlalchemy/enginefacade.py", line 635, in _session
bind=self.connection, mode=self.mode)
File "/usr/local/lib/python2.7/dist-packages/oslo_db/sqlalchemy/enginefacade.py", line 399, in _create_session
File "/usr/local/lib/python2.7/dist-packages/oslo_db/sqlalchemy/enginefacade.py", line 486, in _start
engine_args, maker_args)
File "/usr/local/lib/python2.7/dist-packages/oslo_db/sqlalchemy/enginefacade.py", line 508, in _setup_for_connection
"No sql_connection parameter is established")
CantStartEngineError: No sql_connection parameter is established


Anyone faced the same issue? Can someone help with me this?


  • serewicz
    serewicz Posts: 1,000


    Please look through the installation logs to see if there were any errors with the database. Near the end you can see the CantStartEngineError: No sql_connection parameter is established
    If the same error exists in the main node it is a problem with the overall OpenStack process. If it only exists when a node is added then it may be a bug or some other issue to track down.

    Please also include other errors you find in the installation logs.


  • akshay87
    akshay87 Posts: 8

    Thank you for your quick response.
    Below is the summary of the installation [stack.sh] log found under /opt/stack/logs
    I do not see any error mentioned here..
    The script completed successfully.

  • akshay87
    akshay87 Posts: 8

    Please let me know if there is any other log file that needs to be checked..

  • serewicz
    serewicz Posts: 1,000

    In the command output you pasted it shows that the stack.sh command completed in 660 seconds. But there may be other errors we do not see in this output. Could you grep -i for err messages in the /opt/stack/logs/stack.sh.log* file. The very first line in the output mentions the log file to view.


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