Explanation: DUMPCLASS(class) is an optional parameter of DUMP requesting that each dump copy be targeted to a particular dump class. Dump classes, class, must be predefined with the DUMPCLASS optional parameter of the DEFINE command.
DUMPCLASS is required unless the specified volume is a primary volume with a dump class specified for it with its ADDVOL command. At least one class and no more than five classes must be specified if DUMPCLASS is specified.