BIND 10 #2799: stats lost Auth stats after removing some b10-auth components

[BIND 10 Development]

#2799: stats lost Auth stats after removing some b10-auth components
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            Reporter:  jreed         |                        Owner:
                Type:  defect        |                       Status:  new
            Priority:  medium        |                    Milestone:
           Component:  statistics    |  StatsRedesign
            Keywords:                |                   Resolution:
           Sensitive:  0             |                 CVSS Scoring:
         Sub-Project:  DNS           |              Defect Severity:
Estimated Difficulty:  7             |  Medium
         Total Hours:  0             |  Feature Depending on Ticket:
                                     |          Add Hours to Ticket:  0
                                     |                    Internal?:  0
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Comment (by naokikambe):

 I realized almost the reason of this problem. When one of the multiple
 auth processes receives `shutdown` command, it sends the `stopping`
 message to !ConfigManager.
 {{{
 2013-03-15 17:34:45.230 DEBUG [b10-auth.cc/14779] CC_GROUP_SEND sending
 message '{ "command": [ "stopping", { "module_name": "Auth" } ] }' to
 group 'ConfigManager'
 }}}
 But after that !ConfigManager removes all auth information from its
 internal data, and it no longer manage auth information even though other
 auth processes are running. Also it tells Cmdctl the module which it has
 removed isn't running. That's why `bindctl` didn't recognize an auth's
 command as the above. I suspect this part of `cfgmgr.py` is here.
 {{{#!python
     def __handle_module_stopping(self, arg):
         """Private function that handles a 'stopping' command;
            The argument is of the form { 'module_name': <name> }.
            If the module is known, it is removed from the known list,
            and a message is sent to the Cmdctl channel to remove it as
 well.
            If it is unknown, the message is ignored."""
         if arg['module_name'] in self.module_specs:
             del self.module_specs[arg['module_name']]
             self._send_module_spec_to_cmdctl(arg['module_name'], None)
         # This command is not expected to be answered
         return None
 }}}
 Stats manages information of modules based on data from !ConfigManager. So
 it ignores the module which !ConfigManager doesn't have. I think
 !ConfigManager should check whether other processes of the module which it
 tries to remove are running or not before removing.

-- 
Ticket URL: <http://bind10.isc.org/ticket/2799#comment:4>
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