Oracle Management Service (OMS) is designed to run two types of services, mainly the console services and the background services. While the console services are required to render a GUI-rich console for Enterprise Manager, the background services are required to run critical jobs, upload operations, business logics, and so on.
Figure 15-1 illustrates the functioning of an OMS where both console services and background services are running.
In a multi-OMS environment, if you want to have a dedicated OMS for User Interface (UI) operations or if you do not want to run background services in SSA OMS (external-facing OMS in a private or public cloud environment), then you can choose to shut down the background services and run only the UI services, thus turning the OMS into a pure, console-only mode. In such a case, the Management Agents upload data to other OMS instances where both background services and UI services are running. However, note that you cannot shut down the background services and run only the UI services of an OMS that is deployed in a remote location.
Only the additional OMS instances can be run in console-only mode, while the OMS instance that shares the host with the Administration Server cannot.
Only the additional OMS instances of the same location can be run in console-only mode, while the additional OMS in a remote location cannot. For example, if you have four OMS instances in the US and one in Australia, then the OMS in Australia cannot be run in console-only mode.
Stop the OMS using the following command.
$emctl stop oms
Set the start up mode to console-only, using the following command.
$emctl config oms -set_startup_mode console_only
Start the OMS using the following command.
$emctl start oms
To revert the OMS instances to Normal mode, run the following command, and restart the OMS.
$emctl config oms -set_startup_mode normal