9.12  Online versus Offline Models

  The GCU allows you to display and interact with the ac-
  tive (online) or inactive (offline) Galaxy configuration models.
  When the configuration display represents a model of the
  active system, the GCU displays the state of the CPUs and
  instances using color and text.  When the configuration model
  is engaged in this manner, you can interact with the active
  system using drag-and-drop procedures.  The formal de-
  scription for this mode of operation is interacting with the
  engaged, online model.

  GCU users can also interact with any number of disen-
  gaged, or offline, models.  Offline models can be saved to or
  loaded from files.  An offline model can also be derived from
  the active online model by clicking the Engage button to be
  disengaged when the active online model is displayed.  In ad-
  dition to the visual state of the Engage button, the GCU also
  indicates the online versus offline characteristic of the CPUs
  and instances by using color and text.  Any drag-and-drop
  actions directed at an offline model are interpreted as simple
  editing functions.  They change the internal structure of the
  model but do not affect the active system.

  When an offline model is engaged, the GCU compares the
  structure of the model with that of the active system.  If they
  agree, the offline model is engaged and its new online state is
  indicated with color and text.  If they do not agree, the GCU
  determines what management actions would be required to
  alter the active system to match the proposed model.  A list
  of the resulting management actions is presented to the user
  and the user is asked whether they would like to execute the
  action list.  If the user disapproves, the model remains offline
  and disengaged.  If the user approves, the GCU executes the
  management actions and the resulting model is displayed as
  online and engaged.