While CTM is scheduling requests, it can lock and control requests for a specific schedule queue. Locking and controlling requests for a schedule queue enables service lock, which allows you to replace a specific J2EE application without stopping the system.

Locking and controlling requests of CTM provide the following functions:

• Replacing a J2EE application while the system is online
  You can replace a J2EE application without clearing requests from the schedule queue.
  
• Locking and controlling requests for a J2EE application
  The system waits for requests to finish before locking a J2EE application.
  
• Locking and controlling requests for a schedule queue
  The system immediately locks a schedule queue. At this time, the user can select whether to discard the requests in the queue.
  
• Holding requests if a J2EE server terminates abnormally
  The system holds requests in the schedule queue for a certain length of time if the J2EE server terminates abnormally.
  

To perform locking and controlling requests, use the mngsvrutil management command. For details about this command, see mngsvrutil (Management Server management command) in the uCosminexus Application Server Command Reference Guide.