3400547 - Cannot start MaxDB/liveCache: Too many open files

When you try to start an SAP MaxDB or liveCache database, the following error is shown in KnlMsg or KnlMsgArchive log files when mounting a DATA or LOG Volume:

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Thread     0x20D4 Task     29  2023-11-11 23:29:56     AdminMsg       0:  654FD634009C 0000   RST RESTART
Thread     0x20D4 Task     29  2023-11-11 23:29:56 ERR RTEIO         12:  Attach volume DATA_VOLUME_0010 failed during open,_FILE=RTEIO_VolumeInfo-k+noPIC.cpp,_LINE=1768
                               2023-11-11 23:29:56 ERR RTEIO         87:  volume /sapdb/CS1/sapdata/DISKD0010 cannot be locked:24,ERRORTEXT=Too many open files,_FILE=RTEIO_VolumeInfo-k+noPIC.cpp,_LINE=2736

                                                                           DESCRIPTION:

                                                                           The volume /sapdb/CS1/sapdata/DISKD0010 cannot be locked. The corresponding system call returns the error code 24 : Too many open files.This indicates an overall configuration problem in the database and an access rights problem.

                                                                           ACTION:

                                                                           Contact your system administrator. Show him the error message which points to an operating system configuration error and then contact the database support if your system administrator can not fix the error.
Thread     0x20D4 Task     29  2023-11-11 23:29:56 ERR Admin          3:  Database state: OFFLINE,_FILE=Kernel_Administration+noPIC.cpp,_LINE=1016
                               2023-11-11 23:29:56     KernelComm     6:  Internal errorcode, Error code 9050 "disk_not_accessible"
                               2023-11-11 23:29:56 ERR Admin      20017:  RestartFilesystem failed with 'I/O error',_FILE=Kernel_Administration+noPIC.cpp,_LINE=539
Thread     0x20B0 Task      -  2023-11-11 23:29:57 ERR Messages       7:  Begin of dump of registered messages,_FILE=Msg_Registry+noPIC.cpp,_LINE=507
Thread     0x20B0 Task      -  2023-11-11 23:29:56     KernelComm     6:  Internal errorcode, Error code 9050 "disk_not_accessible"
Thread     0x20B0 Task      -  2023-11-11 23:29:56 ERR Admin          3:  Database state: OFFLINE,_FILE=Kernel_Administration+noPIC.cpp,_LINE=1016
                               2023-11-11 23:29:56     KernelComm     6:  Internal errorcode, Error code 9050 "disk_not_accessible"
                               2023-11-11 23:29:56 ERR Admin      20017:  RestartFilesystem failed with 'I/O error',_FILE=Kernel_Administration+noPIC.cpp,_LINE=539
Thread     0x20B0 Task      -  2023-11-11 23:29:57 ERR Messages       8:  End of the message list registry dump,_FILE=Msg_Registry+noPIC.cpp,_LINE=544
Thread     0x20A6 Task      -  2023-11-11 23:29:58 ERR RTEKernel    102:  Kernel exited without core and exit status 0x200,_FILE=RTEKernel_Termination+noPIC.cpp,_LINE=704
Thread     0x20A6 Task      -  2023-11-11 23:29:58 ERR RTEKernel    106:  Kernel exited with exit code 0x2,_FILE=RTEKernel_Termination+noPIC.cpp,_LINE=782

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Or you see messages similar to:

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Thread     0x7D00 Task      -  2024-02-25 16:25:22 ERR IO         11834:  Can't open('/sapdb/data/ipc/us:<SID>/FIFO-2445.196796' mode 0x2), 'Too many open files'
Thread     0x7D00 Task      -  2024-02-25 16:26:02 ERR IO         11834:  Can't open('/sapdb/data/ipc/us:<SID>/FIFO-15581.65539' mode 0x2), 'Too many open files'
Thread     0x7D00 Task      -  2024-02-25 16:27:22 ERR IO         11834:  Can't open('/sapdb/data/ipc/us:<SID>/FIFO-2445.196797' mode 0x2), 'Too many open files'
Thread     0x7D00 Task      -  2024-02-25 16:29:22 ERR IO         11834:  Can't open('/sapdb/data/ipc/us:<SID>/FIFO-2445.196798' mode 0x2), 'Too many open files'
Thread     0x7D00 Task      -  2024-02-25 16:30:07 ERR IO         11834:  Can't open('/sapdb/data/ipc/us:<SID>/FIFO-16736.65536' mode 0x2), 'Too many open files'
Thread     0x7D00 Task      -  2024-02-25 16:31:22 ERR IO         11834:  Can't open('/sapdb/data/ipc/us:<SID>/FIFO-2445.196799' mode 0x2), 'Too many open files'
Thread     0x7D00 Task      -  2024-02-25 16:33:22 ERR IO         11834:  Can't open('/sapdb/data/ipc/us:<SID>/FIFO-2445.196800' mode 0x2), 'Too many open files'
Thread     0x7D00 Task      -  2024-02-25 16:34:12 ERR IO         11834:  Can't open('/sapdb/data/ipc/us:<SID>/FIFO-16736.65537' mode 0x2), 'Too many open files'

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• MaxDB >= 7.6
• SAP liveCache >= 7.7
• UNIX Operating system

open files maxdb user limit liveCache unix nofiles disk_not_accessible , KBA , BC-DB-SDB , MaxDB , BC-DB-LVC , liveCache , Problem