IZ3293: *_command can contain NONE, but it still tries to start

[reuti]

[Imported from gridengine issuezilla ​http://gridengine.sunsource.net/issues/show_bug.cgi?id=3293]

        Issue #:      3293             Platform:     All      Reporter: reuti (reuti)
       Component:     gridengine          OS:        All
     Subcomponent:    qmaster          Version:      6.2u5       CC:    None defined
        Status:       NEW              Priority:     P3
      Resolution:                     Issue type:    DEFECT
                                   Target milestone: ---
      Assigned to:    ernst (ernst)
      QA Contact:     ernst
          URL:
       * Summary:     *_command can contain NONE, but it still tries to start
   Status whiteboard:
      Attachments:

     Issue 3293 blocks:
   Votes for issue 3293:


   Opened: Mon Nov 22 05:36:00 -0800 2010 
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The entries in SGE's configuration for the commands of the three remote startup methods qlogin_command, rlogin_command and rsh_command can
contain the value NONE. This implies, that this communication method should be disabled. Nevertheless the corresponding daemons are started
and finally the e.g. `qrsh` call returns with an error.

When a *_command of NONE is defined, the client program for this communication method should fail instantly with an appropriate message,
stating something like "qrsh not available" or alike.