Command > cleanipc remove. Example: cleanipc 50 remove (if the instance number is J50)

You  can use command cleanipc to clear or delete the old shared memory, semaphores and events flags from the operating system for SAP system. You need to logged as SID adm to authorized use of cleanipc. The command is cleanipc NN remove. NN is stand for system number.

> cleanipc NN remove

Show/Cleanup SAP-IPC-Objects V2.3, 94/01/20
===========================================

Running SAP-Systems (Nr)...:

----------------------------------------------------------
---- Clear IPC-Objects of Sap-System  7 ------------------
----------------------------------------------------------
OsKey:    10734 0x000029ee Shared Memory Key: 34 removed
OsKey:    20726 0x000050f6 Semaphore Key: 26 removed
OsKey: 58900107 0x0382be8b SCSA Shared Memory Key: 58900000 removed

Number of IPC-Objects...........:    3
Number of removed IPC-Objects...:    3

You will need to execute the command again to make sure the number of removed IPC-Objects is 0.

> cleanipc NN remove

Show/Cleanup SAP-IPC-Objects V2.3, 94/01/20
===========================================

Running SAP-Systems (Nr)...:

----------------------------------------------------------
---- Clear IPC-Objects of Sap-System  7 ------------------
----------------------------------------------------------

Number of IPC-Objects...........:    0
Number of removed IPC-Objects...:    0