Tuts4Tech

This tutorial will show you how to set up a serial console on a Linux system, and connect to it via a null modem cable. This is quite useful as it allows you to easily get a console on the system if there are any problems with it and you cannot access it via ssh

Check that you have a serial port and it is enabled in your bios

dmesg | grep tty

root@duffys-place:~# dmesg | grep tty
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
00:09: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A

Configuring Lilo

1. open up /etc/lilo.conf

   nano /etc/lilo.conf

2. Find the the serial line and change it to the following:

   serial=0,38400n8

3. Now edit your kernel settings so they include the line

   append="console=ttyS0,38400n8"

   It should look something like this

   default=Linux
   image=/vmlinuz
           label=Linux
           append = "console=ttyS0,38400n8"
           initrd=/initrd.img

4. Run /sbin/lilo to apply the changes

Enable Logins

1. Open up /etc/inittab

   nano /etc/inittab

   and add the following line

   T0:2345:respawn:/sbin/getty -L ttyS0 38400 vt100

Testing It

1. Plug one end of your null modem cable into your server and the other into your computer
2. Open your terminal client i used putty hyperterminal works fine too
3. Use the following settings:

   Port: COM1 or COM2(what ever your serial port is)
   Bits per second: 38400
   Data bits: 8
   Parity: None
   Stop bits: 1
   Flow control: None

4. You should be able to see your console. If you have any issues feel free to leave a comment