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We have a bunch of Apple xservers but only one of them has VGA output and CD Drive. We've decided to replace OSX with Debian Linux (Squeeze for ppc). Meanwhile, my efforts to get the machines send output to serial port have never succeeded. So, I installed Debian on the only machine with VGA and CD Drive and then cloned its disk image (using dd) on other machines' HDD, expecting everything to work since the machines have the exact same hardware. When I turn on a machine with a cloned disk image (no VGA and serial output, so my only means of communicating with the machine is ping/ssh) I see the machine boots and acquires an IP address from the DHCP server because I can ping it. However networking services, specially ssh fail to start on the machine (a port scan does not show any open port). Now if I attach the same HDD to the node with VGA and CD drive, it boots perfectly and everything works. It seems the networking services are sensitive to this change in hardware. But I have no idea how to fix this.

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Do you see anything in the log files when mounting the disks on another machine afterwards? –  SvW Oct 28 '11 at 13:06
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1 Answer

Why not using a laptop with GtkTerm or minicom (exemple), a usb/serial cable and sending the kernel console to serial ?

Append to kernel definition that should use serial console (from Grub prompt):

 console=ttyS0,9600n8

Or follow the entire How To:

On your server, configure redirecting GRUB screen: edit the file ‘/boot/grub/menu.lst’:

# vi /boot/grub/menu.lst

and add this a the top:

serial --unit=0 --speed=38400 --word=8 --parity=no --stop=1 
terminal --timeout=10 serial console

Save and Quit the file. Restart your server.

On your laptop, launch a terminal emulator like minicom (if on Linux) or HyperTerminal (if on Windows). FI am assuming that we are using the minicom program on machine running Linux. To launch minicom type in:

 # minicom

Make sure that the serial port is configured with following settings (You can do this by pressing Ctrl+A and then press ‘z’ key. And then press ‘o’ key and navigate to “Serial Port Setup” option.):

 A -    Serial Device      : /dev/ttyS0
 E -    Bps/Par/Bits       : 38400 8N1

Finally you can login in your server even with network failure !

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