Dataguard parameter changed after DB bounce
The initialization parameters are not supposed to change while bouncing the database except in one case, that is if the modification was only for currently running instance(SCOPE=MEMORY).

The following are the steps to modify initialization parameters using Enterprise Manager.



  To modify initialization parameters for the currently running instance, and also record the modifications in the server parameter file that will persist when the database is restarted, complete the following steps:
  On the Current subpage, in the Value column, enter new values for the initialization parameters.
  Select Apply changes in current running instance(s) mode to SPFile.
  (Optional) In the Comments column, enter text explaining the reasons for the changes.
  Click Apply.
  A confirmation message appears.
  


Viewing and Modifying Initialization Parameters