March 2005 Archives

LC_ALL=C mkisofs -b isolinux/isolinux.bin -c isolinux/boot.cat \
    -no-emul-boot -boot-load-size 4 -boot-info-table -r -J -T \
    -v -v -V "RHEL/3 i386" -o rhel-3-U3-i386-as-dvd.iso install

diff --exclude='*.orig' --exclude='*.o' --exclude='*.ko' \
    --exclude='*.cmd' --exclude='*.o' --exclude='CVS' \
    --exclude='.svn' --exclude='*.mod' --exclude='.*' \
    --exclude='*.rej' --exclude='*.orig' --exclude='*.symvers' \
    --exclude='debian' --exclude='*.a' --exclude='*.mod.c' \
    --exclude='System.map' --exclude='*.so' -urN \
    a b >different.patch

Assume there are two machines, station1 and station2.  There is a serial cable between ttyS0 on each of two machine.

On station1

Set up station1 to output various messages to serial port.

1. Set up grub, make grub menu output to the serial port.
Add the following lines into /boot/grub/menu.lst.

serial --unit=0 --speed=115200
terminal --timeout=10 serial console

If there is a gfxmenu option in menu.lst, remove it.  For the system cannot display graphic via serial port.

#gfxmenu (hd0,0)/boot/message

2. Set up linux kernel, make serial port to be default console.
Modify /boot/grub/menu.lst.  Add the following options to kernel parameter.

console=ttyS0,115200 console=tty0

3. Set up init, to provide serial port login.
Add the following line into /etc/inittab

S0:12345:respawn:/sbin/agetty -L 115200 ttyS0 vt102

To make this modification become effective immediately, run the following command.

kill -HUP 1

4. Set up pam module, so that root can login via serial port
Add the following line at the end of /etc/securetty.

ttyS0

On station2

Setup the serial communication program, minicom on station2, which at the other end of serial cable.

5. Run the following commands at shell prompt on station2.

minicom -s

6. Select "Serial port setup" from the drop down menu and press Enter.  Press "A", set Serial Device to "/dev/ttyS0".  Press "E", "I" and ESC.  This set Bps/Par/Bits to 115200 8N1.  Press ESC to return to the main menu.

7. Select "Modem and dialing" and press Enter.  Press "A" and set Init string to ""(null string).  Press "B" and set Reset string to ""(null string).  Press ESC to return to the main menu.

8. From the main menu, select "Save setup as dfl", then "Exit from Minicom".

Now, you can access the station1 via serial port from station2.

9. Run the following command on station2.  Try to login and reboot the system.

minicom

Happy to see "uncompressing linux.................. done, booting the kernel...." from serial console.