Switching a Log File

When a log switch occurs, the log writer (LGWR) process stops writing to the current online redo log group and starts writing to the next available redo log group. After a log switch, the current online redo log group becomes inactive, and the next available online redo log group becomes the current online redo log group. You can switch a log file using Oracle Enterprise Manager Database Express (EM Express).

You can force a log switch to make the current redo group inactive and available for redo log maintenance operations. Forcing a log switch is useful in configurations with large redo log files that take a long time to fill. For example, you might want to:

  • Drop the current redo group, but are not able to do so until the group is inactive

  • Archive the current online redo log group members immediately, even though they are not yet completely filled

To switch a log file:

  1. In EM Express, from the Storage menu, select Redo Log Groups.

    The Redo Log Groups page appears.

  2. From the Actions list, select Switch Logfile, and then click OK.

    A confirmation message appears.

  3. A confirmation message appears. Click Yes.

    The status of the group that had been Current changes to Active, and the status of the next group in the list changes from Active to Current.