In this module we covered the noarchivelog and archivelog modes. We discussed how to manage a database that is set up in
noarchivelog mode and the types of recovery options available to you.
We then turned to the use of archivelog mode and the beginning steps to setup your database to archive the redo log files.
By now you should be comfortable with the following:
- The differences between physical and logical backups
- The differences between online and offline backups
- The differences between archivelog and noarchivelog mode
- Operating a database in noarchivelog mode
- Configuring a database for archivelog mode and automatic archiving
- Configuring a database for duplex archivelog mode
Clearly there are advantages and disadvantages to noarchivelog and archivelog mode.
The recommendation it to use archivelog mode whenever possible. The benefits of media recovery greatly out weight
any additional disk space required supporting the use of archivelog mode. Before continuing our discussion on the archiving of redo log files in the next module, please take a moment to complete the
quiz and exercise. The following sidebar contains a table which lists all the init.ora parameters that we have covered up to this point.
| init.ora parameter | Description |
|---|
LARGE_POOL_SIZE | This is how you create the Large Pool. When the Instance starts, it will allocate the requested memory in the SGA. |
LARGE_POOL_MIN_ALLOC | This is the smallest chunk that will be allocated. |
ARCH_IO_SLAVES | This is the number of I/O slaves used for log archiving. |
BACKUP_DISK_IO_SLAVES | This is the number of I/O slaves used by RMAN for copy, backup, and restore. |
BACKUP_TAPE_IO_SLAVES | If True, then one I/O slave is used to perform asynchronous I/O to and from tape when doing an RMAN backup and restore. |
LOG_ARCHIVE_DEST | This parameter will indicate where the archive log files will be written. |
LOG_CHECKPOINT_INTERVAL | This parameter will cause a checkpoint when the specified number of OS blocks have been written to the redo log files since the lastcheckpoint. |
LOG_CHECKPOINT_TIMEOUT | This parameter will cause a checkpoint when the specified number of seconds has elapsed since the last checkpoint. |
USER_DUMP_DEST | This is the directory that will contain the output from your trace commands. |
LOG_ARCHIVE_DEST | This is the location for archive log files. |
LOG_ARCHIVE_FORMAT | This is the format of the name for the archive log files. |
LOG_ARCHIVE_DUPLEX_DEST | This is the location for duplexed archive log files. |
LOG_ARCHIVE_MIN_SUCCESS_DEST | If your are duplexing your archive log files, this shows how many of the destination archive log files must succeed either 1 or 2. |