Install, Configure, and Run - Oracle WebLogic Server 12c Advanced Administration - page 15

3. Make the necessary changes and click on the Save button to save it.
4. If there are any configuration changes pending, the Lock & Edit button should be
labeled now as Activate Changes:
5. Click on the Activate Changes button to confirm the changes.
How it works...
All saved changes made before activating the session are saved in the $DOMAIN_HOME/
pending directory. It contains the new version of the configuration files ( config.xml ).
As soon as the Activate Changes option is clicked on, the Administration Server issues a
command to all the WebLogic Managed Server instances to update the configuration. If any of
the Managed Servers do not accept the new configuration, the changes are rolled back and
the Administration Console will show a message. If the new configuration is accepted by the
Managed Servers, the changes will be activated and the configuration files will be updated by
all the servers and one very machine belonging to the domain.
There's more...
The system administrator can also make configuration changes through WLST.
Making changes using the WLST
Under the hood, WebLogic Server uses a JMX framework that exposes WebLogic MBeans to
manage its configuration. The Administration Console issues JMX commands as you make
changes to Configuration Manager MBean. MBeans can be accessed through WLST.