Manage
the Online Redo Log
Before You Begin
This 15-minute tutorial shows you how to manage the online redo log files.
Select the Oracle Database release:
Background
An Oracle database is made up of physical and logical structures. Physical structures are visible in the operating system. An example of a physical structure is an operating system file that stores data on a disk. Logical structures are defined and known to the Oracle Database server, but are not known to the operating system. An example of a logical structure is a tablespace. In this tutorial you will view logical structures in your database and understand how they relate to physical structures in the operating system.
What Do You Need?
- Oracle Database 18c19c
Multiplex
the Redo Log File
The online redo log files contain entries that are used to recover transactions in the event of an instance failure and may also be used in recovery from media failure. To ensure that redo entries are not lost in the event of a disk drive failure, redo log files should be multiplexed so that each group has multiple members.To multiplex the redo log file, perform the following steps:
- Select "Redo Log Groups"
in the Storage menu.
Description of the illustration a1 - Select the first redo log group and click "Add
Member."
Description of the illustration a2 - Enter a directory location in the File Directory field and a
file name in the File Name field. Click OK.
Note that redo log file members should be stored on separate
disk drives so that at least one member will be accessible if
you have a disk drive failure.
Description of the illustration a3 - Click OK on the
Confirmation page.
Description of the illustration a4 - The Redo Log Groups page shows the new member in Redo Log
Group 1.
Description of the illustration a5 - Repeat steps 2 through 4 for log groups 2 and 3. The Redo
Log Groups page should now show that each group has two
members.
Description of the illustration a6 - Click ORCL to return to the Database Home page.