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Serial Connection

On Mon, 21 Mar 2011 at 17:45:17 +0100, MAROUNI Abbass wrote:
> I have two servers with Debian Lenny installed.
> The two servers have a serial cable connected form Stty0 on Server0
> to Stty1 on Server1.  I can use minicom to log into Server0, but when
> I try to login to Server1 from Server0 using minicom I get some garbage
> and I can't type anything with the keyboard.
> Any Ideas??

I haven't tried this, but one thing you want to make sure of is that
you use a "cross-over" cable.  The serial ports on PCs have what's known
as a DTE interface (Data Terminal Equipment).  The serial ports on
modems have what's known as a DCE interface (Data Communications
Equipment).  A standard serial cable is designed to connect a DTE
interface to a DCE interface (i.e. a computer to a modem).
What you are trying to do is connect two DTE interfaces together.
For that you need to use a special serial cable called a "cross-over"
cable which is specifically designed to connect a DTE interface to
another DTE interface.  If you try to use a regular serial cable,
one designed to connect a DTE interface to a DCE interface, it won't work.

An alternative to using a cross-over cable is to use a device called
a "null modem" on one end of your serial cable.  A null modem attached
to a standard serial cable effectively converts it into a cross-over

Connecting a serial printer to a computer also requires a cross-over
cable or a standard cable plus a null modem, since both devices have
a DTE interface.

You also might have to use two cables and two serial ports.  One serial
port looks like a modem, with you as the terminal.  minicom
allocates it.  The other serial port looks like a serial console,
with you as the host.  getty allocates it.  The other server sees
a similar pattern.

  .''`.     Stephen Powell    
 : :'  :
 `. `'`

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