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  • Dbvisit Standby either leaves primary redo names unchanged in the standby control file, or sets the Oracle parameter log_file_name_convert in the standby database parameter file (spfile) to change redo locations

  • Using the log_file_name_convert parameter can also be used to get rid of error messages in the standby alert log caused by having references to ASM redo in the control file while no ASM storage available on the standby database
  • If using ASM on the standby database, references to standby redo are created as the ASM Disk Group.  Example if the Disk Group is +DATA the value will be set to '+DATA'. This ensures redo Note that redo logs are not used when the standby database is in recovery mode.  By adjusting the redo log names to the Disk Group names, on activation the redo logs are created as ASM_FQSN in case of Activation or Graceful Switchover FQSN 
  • If using ASM on the Primary, but not using ASM on the standby database, a reference to a standby redo log is created as OMF if the primary database redo log is OMF (FS or ASM), and as non-OMF if a primary database redo log is non-OMF.

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  • Dbvisit creates an OMF temp file if a primary temp file is OMF of ASM_FQSN. Creation of OMF files must be enabled on the standby.on the standby - this is done by setting Oracle parameters db_create_file_dest, db_create_online_log_dest_n and db_recovery_file_dest (see Oracle documentation for more detail on the use of OMF files)
  • Dbvisit creates a FS temp file if a primary temp file is FS or ASM_ALIAS. 

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Dbvisit uses the following algorithm to determine location of redo logs on the new primary database during Graceful Switchover (in this particular order):

    1.  The first option is to use the location defined by variable DEFAULT_STDBY_REDO_LOC if set in a DDC file, otherwise
    2. Use OMF locations if creation of OMF files enabled - this is done by setting Oracle parameters db_create_file_dest, db_create_online_log_dest_n and db_recovery_file_dest (see Oracle documentation for more detail on the use of OMF files), otherwise
    3. Use redo locations referenced in the old standby control file, if storage type matches. For example, if the new primary does not use ASM storage, and the old standby control file referenced ASM redo logs, these location cannot be used; otherwise
    4. Default to use the location of the first SYSTEM datafile as the last option
  • Redo base names on new primary

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