This tutorial is for those Admins who need to setup serial console on there LINUX servers


Section-1

1. In this first part of of the how to I will show you how to setup serial console on a
   RedHat(Fedora,CentOS) based systems(Does work on other systems as well).
   • First step is to make sure you have a serial port.
   • Second step is to make sure you have a console cable. You can do this by running this..
     
     

     linuxdynasty.org]# dmesg |grep ttyS0
     ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
       

2. Once you verified you have the necessary hardware configuration,
   we are on to configuring the server.
   • Add this co:2345:respawn:/sbin/agetty ttyS0 9600 vt100-nav to /etc/inittab
     using your favorite editor. (mine is vi :) ) This is how mine looks like..
     

     # Run gettys in standard runlevels
     co:2345:respawn:/sbin/agetty ttyS0 57600 vt100-nav
     1:2345:respawn:/sbin/mingetty tty1
     2:2345:respawn:/sbin/mingetty tty2
     3:2345:respawn:/sbin/mingetty tty3
     4:2345:respawn:/sbin/mingetty tty4
     5:2345:respawn:/sbin/mingetty tty5
     6:2345:respawn:/sbin/mingetty tty6
      

3. Now it is time to edit /boot/grub.conf. These two entries need to be added into grub.conf
   serial --unit=0 --speed=57600
   terminal --timeout=5 serial console
   And append this to console=ttyS0,57600n8 to your kernel entry.
   • Here is the all in one solution..
     
     

     
     serial --unit=0 --speed=57600
     terminal --timeout=5 serial console
     title CentOS (2.6.9-55.0.2.EL)
        root (hd1,0)
        kernel /vmlinuz-2.6.9-55.0.2.EL ro root=/dev/VolGroup00/LogVol00 console=tty0 console=ttyS0,57600n8
        initrd /initrd-2.6.9-55.0.2.EL.img
       

   • Now reboot your server and from another box console in.

Section-2

1. Now we will show you how to setup a serial console for Ubuntu Feisty 7.0.4,
   (Reason I chose Feisty is that Feisty no longer uses the /etc/inittab .
   Instead uses upstart for its init functions)
   • First step, follow the First step in Section-1 of this tutorial.

2. Once you verified you have the necessary hardware configuration,
   we are on to configuring the server.
   • Add this exec /sbin/getty -L 57600 ttyS0 vt102 to /etc/event.d/ttyS0 (
     If this file does not exist please create it) using your favorite editor. (mine is vi :) )
     This is how mine looks like..
     
     

     # tty0 - getty
     #
     # This service maintains a getty on tty1 from the point the system is
     # started until it is shut down again.
     
     start on runlevel 2
     start on runlevel 3
     start on runlevel 4
     start on runlevel 5
     
     stop on runlevel 0
     stop on runlevel 1
     stop on runlevel 6
     
     respawn
     exec /sbin/getty -L 57600 ttyS0 vt102
       

3. Now proceed to third step of Section-1 of this tutorial.