The command you run shows the free physical disk space within the Symmetrix array as it can be  used to create new Symmetrix devices for different emulation modes. `  Free disk space on unformatted disks is shown as available for all emulation modes. If a physical disk has been partially used to create a device, that device is considered formatted and the rest of the available space can only be used fordevices of the same emulation mode. Free disk space on unformatted disks is shown as available for all emulation modes.New Symmetrix devices will be created first on physical disks that have no prior allocations, causing these disks to be committed to that emulation type.  The freespace in a disk group on a Symmetrix can be checked by issuing the following command:  symdisk -sid XXX list -dskgrp_summary    Check out support article [URL] Also check out the array controls CLI guide  IBM FBA and Unisys FBA are legacy outputs I believe from DMX days.  Note they report the same values as FBA.  
As I know, this command should show me the free space: symconfigure list -free -sid 123    Emulation               Formatted    Unformatted                                 (Cyl)          (Cyl)     ---------------------   ---------    -----------     FBA                        424448       23453200     IBM_FBA                    424448       23453200     UNISYS_FBA                 424448       23453200     CKD-3390                   480064       26803200  I know FBA is for open systems, and CKD for mainframe. 424448 cyl = 424448X960= 407470080K=388GB; 23453200=20TB Now, following are my questions:   1.     What is IBM_FBA and UNISYS_FBA, are these defined by binfile, or by users? 2.     Does "free space" really mean how much free space left on the array? 388GB seems too small. 3.     I believe "Formatted" and "Unformatted" are referring to different part of space, if is, then which part exactly are they, respectively?  Please help!
How to interpret the result of symconfigure list -free -sid 123