If your BIOS uses this technique or you choose to set Cease redirection after boot then you should:
The BIOS cannot be accessed from the serial port, so power-on self-test messages cannot be seen.
If you need to configure the boot loader to use the serial port then continue to Chapter 4. Otherwise go to directly to Chapter 5 to configure the kernel; this is done by configuring the boot loader to pass boot parameters to the Linux kernel.