With variable logging, the block size must be set to 32760.
This option is available for all DASD, except that in z/VSE a device defined as FBA may not be initialized as variable.
Spanned logging cannot be used for a variable LXX.
Variable logging is provided for the LXX. It is not supported for the Force Area (FXX). The FXX does not need to be initialized, however, when fixed logging is converted to variable logging.
