If the properties you change require restart, plan for the required downtime while the AS Java restarts.
Expert mode of the user management configuration tool enables you to change user management engine (UME) properties online at the global level. Use expert mode to configure UME properties for which there is no other user interface.
If you cannot start SAP NetWeaver Application Server (AS) Java, use the config tool.
For more information, see Editing UME Properties Offline .
Do not edit undocumented properties without consulting SAP Support.
For more information, see Configuring User Management .