IBM Midrange System DS4000 Series Hardware Manual page 259

The operating systems that support a dynamic increase of capacity in a mapped logical drive
are:
AIX
Linux
NetWare
Windows Dynamic Disks
Windows Basic Disks
Tip: If a logical drive-to-LUN mapping has not yet been defined, it is possible to increase
the capacity for a standard logical drive on any host operating system, that is, before host
system data is placed on the drive.
The storage capacity of a standard logical drive cannot be increased if:
One or more hot spare drives are in use in the array that it resides on.
The logical drive has
Any logical drive in the array is in any state of modification.
The controller that owns this logical drive is in the process of adding capacity to another
logical drive (each controller can add capacity to only one logical drive at a time).
No free capacity exists in the array and no unconfigured capacity (in the form of drives) is
available to be added to the array.
To increase the logical drive capacity, on the SM Logical/Physical view, highlight the logical
drive to be expanded, right-click it, and select Increase Capacity. In the Increase Logical
Drive Capacity window (Figure 4-106), enter the amount of space by which the logical drive
will be enlarged.
Figure 4-106 Dynamic logical drive expansion
In the top part of the window shown in Figure 4-106, the current size of the logical drive and
the available free capacity in the array is displayed. If no free configured space is available,
but there are unassigned drives, these can be added from this same window by clicking Add
Drives before proceeding to enlarge the logical drive. This will perform the same process
described in 4.10.1, "Expanding arrays" on page 233.
Non-Optimal
status.
Chapter 4. IBM System Storage DS planning and configuration
241