Use the vi editor to open the /etc/inittab file and add S0:12345:respawn:/sbin/agetty -L 115200 ttyS0 to the end of the file.
Use the vi editor to open the /boot/grub/menu.lst file, locate hiddenmenu, and add the following information to the end of the gfxmenu (hd0,1)/boot/message:
serial --unit=0 --speed=115200
terminal --timeout=5 serial console
Then add the following information to the end of the kernel row:
console=tty0 console=ttyS0,115200n8
To enable user root to log in to the BMS through the serial port, add ttyS0 to the end of the security configuration file /etc/securetty.
