Dear all,
the problem is solved by DB2's privilege, thanks !
Backup_Dev:Database Backup to Device
Backup_Dev:started by CL_DB6_JOB_BACKUP_DEVICE
Backup_Dev:Parameter TESTMODE has not been set
Backup_Dev:Parameter RUNTIME has not been set
Backup_Dev:Parameter BACKUP_MODE has been set to "ONLINE"
Backup_Dev:Parameter PARTITION has not been set
Backup_Dev:Parameter BACKUP_TYPE has been set to ""
Backup_Dev:Parameter COMPRESS has been set to "COMPRESS"
Backup_Dev:Parameter INCLUDE LOGS has been set to "INCLUDE LOGS"
Backup_Dev:Parameter NUMBER_BUFFERS has been set to " 0"
Backup_Dev:Parameter BUFFER_SIZE has been set to " 0"
Backup_Dev:Parameter PARALLELISM has been set to " 0"
Backup_Dev:Parameter UTIL_IMPACT_PRIORITY has not been set
Backup_Dev:Parameter FILE_PATH has been set to "/db2_backup/dbbk"
Backup_Dev:BACKUP DATABASE Q19 ONLINE TO"/db2_backup/dbbk" COMPRESS INCLUDE LOGS
Backup_Dev:finished