Boston Linux & Unix (BLU) Home | Calendar | Mail Lists | List Archives | Desktop SIG | Hardware Hacking SIG
Wiki | Flickr | PicasaWeb | Video | Maps & Directions | Installfests | Keysignings
Linux Cafe | Meeting Notes | Blog | Linux Links | Bling | About BLU

BLU Discuss list archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Serial Port networking

It turns out my parallel port cable wasn't a crossover cable after all :(

So now I'm trying with a brand new serial port crossover cable.  I know this
one works because when I type:
cat /dev/ttyS0 on my laptop
ls > /dev/ttyS1 on my desktop
the directory listing appears on the laptops display.  So this tells me that
both serial ports work, and the cable does what it's suppose to. :)

Now I ran across this post on in the network section:

"To start you need a null modem cable (rs232 cable) and a free serial-port on
each of the computers that will be networked.  After the cable is connected
to both computers, all you need to do is run the following command on each of
the computers. /sbin/slattach -p cslip -s {speed} {serial port} &
/sbin/ifconfig sl0 {IP of host system} pointopoint {IP of other system} up Now
you have networked your two computers. "

So I figured I'd try it (one step at a time to begin with)
On the desktop I run:
slattach -p cslip -s 2400 /dev/ttyS1  (what speed can a serial port handle anyway?) 
then check ifconfig -a and sure enough a new (inactive)
device called sl0 is there.

I repeat this on the laptop but using ttyS0 instead and get the same results,
so far so good.

Next I run:
ifconfig sl0 pointtopoint up (desktop)
ifconfig sl0 pointtopoint up (laptop)
on the desktop I get this
pointtopoint: Unknown host

and on the laptop I get this:
pointtopoint: Host name lookup failure

So I checked the man page and pointtopoint specifies the other end of the
IP address of the other end of the connection.  Now does it specify the IP
address so that it knows where to send it, or so that it knows to send packages
for that IP across this connection?

Now something that bothers me is when I run the ifconfig command on the desktop,
the lights on my cable modem blink.  So it seems that it is doing _something_
with eth0

does anyone have any ideas?


Frank J. Ramsay
fjr at

Subcription/unsubscription/info requests: send e-mail with
"subscribe", "unsubscribe", or "info" on the first line of the
message body to discuss-request at (Subject line is ignored).

BLU is a member of BostonUserGroups
BLU is a member of BostonUserGroups
We also thank MIT for the use of their facilities.

Valid HTML 4.01! Valid CSS!

Boston Linux & Unix /