VMS Help SET, MAGTAPE, Qualifiers, /LOGSOFT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /LOGSOFT (default)
       /NOLOGSOFT

    Controls whether soft errors on the specified device are to be
    logged in the error log file. Soft errors are errors corrected
    by the hardware without software intervention. This qualifier
    affects only devices that support hardware error correction, such
    as the TU78 magnetic tape drive. When used with other devices,
    this qualifier has no effect.