boot-file
    Specifies the filename of the boot file for the target disk.
    Architecture-specific defaults are applied for the
    boot file. For Integrity servers, the default is
    SYS$SYSROOT:[SYS$LDR]SYS$EFI.SYS (SYS$EFI).
    The boot file must be contiguous. If the target boot file is
    not contiguous, use the DCL command COPY/CONTIGUOUS or another
    functionally similar mechanism to recreate a contiguous version
    of the boot file.
    The boot file must also be marked NOMOVE (using the DCL command
    SET FILE/NOMOVE) to avoid a bootstrap failure that could result
    from the normal and expected operations of disk defragmentation
    tools.