Automatic dynamic volume expansion space management
Certain DASD controllers have the ability to dynamically change the size of a logical volume. After the size of a volume is dynamically changed, the ICKDSF REFORMAT command must be run to rebuild the VTOC and INDEX on the volume. Until this is done, DFSMShsm will not be aware of the new volume size. After the REFORMAT has been processed, DFSMShsm automatically updates its volume records so that future processing will use the new volume size.
Note: DFSMShsm only gets notified of volume changes when
the VTOC REFORMAT is done on the same sysplex. If done on another
sysplex, DFSMShsm is not notified and will continue to use the original
size until DFSMShsm is restarted.