Serial port to serial port with null modem cable

Serial port to serial port with null modem cable

Post by Todd Walla » Tue, 01 Apr 1997 04:00:00



I am trying to get uucp to work between two Linux machines with their
/dev/cua0 connected with a null modem cable.

What is a simple test to see if traffic can go back and forth on this cable?

Thanks,
Todd Wallace

 
 
 

Serial port to serial port with null modem cable

Post by S. Yode » Wed, 02 Apr 1997 04:00:00




Quote:> I am trying to get uucp to work between two Linux machines with their
> /dev/cua0 connected with a null modem cable.

> What is a simple test to see if traffic can go back and forth on this
cable?

Todd,

You might want to look for the Waffle BBS FAQ. It's mostly MS-DOS but
definitely UUCP related. Somewhere I remember seeing this setup
& how its done to get UUCP talking to UUCP. You may also want to
do a search on UUCICO.

If I was at work I'd give you the URLs... if you want them
email me & I'll bring them home.

Enjoy,
Stef
--
the 2 is for, ya know... kill it to email me
"Ah, Jedi master! Yoda. You seek Yoda!"
http://www.netcom.com/~yodersj/


 
 
 

Serial port to serial port with null modem cable

Post by Michail Brzitw » Wed, 02 Apr 1997 04:00:00




Quote:> I am trying to get uucp to work between two Linux machines with their
> /dev/cua0 connected with a null modem cable.
> What is a simple test to see if traffic can go back and forth on this cable?

On one end, let some getty take over the line (e.g. 'agetty -L ttyS0
38400 linux'), on the other end start the cu program ('cu -l ttyS0
-s 38400'), and try to log in.
--

 
 
 

Serial port to serial port with null modem cable

Post by Jon Haugsan » Wed, 02 Apr 1997 04:00:00



> I am trying to get uucp to work between two Linux machines with their
> /dev/cua0 connected with a null modem cable.

> What is a simple test to see if traffic can go back and forth on this cable?

One machine: yes >/dev/cua0
Other:       cat /dev/cua0

If not y's appear you have some problem.

--
Jon Haugsand

  http://www.ifi.uio.no/~jonhaug/, Pho/fax: +47-22852441/+47-22852401

 
 
 

Serial port to serial port with null modem cable

Post by Olivie » Wed, 02 Apr 1997 04:00:00



> I am trying to get uucp to work between two Linux machines with their
> /dev/cua0 connected with a null modem cable.

> What is a simple test to see if traffic can go back and forth on this cable?

try to find uugetty or agetty and you put this in your /etc/inittab:
s1:12345:respawn:/sbin/agetty 19200 ttyS1 vt100
(or the equivalent you need)
and you're able to log in remotely..

cu,
        Olivier

 
 
 

1. Serial ports and Null modem cables....

Here's the story.....

For about *2 months* I've been tying to connect my two Linux boxes with
a Null modem cable.  Heres a look at the revelent line in my inittab:

          s2:45:respawn:/sbin/agetty 38400 ttyS1 vt100

This line would generate no errors in the logfiles and 'ps ax' shows
that the getty is runing as it should. when I go to the other box and
run minicom or seyon or cu however, there is never a connection. ONE
time it did get a login prompt, but then the terminal froze.  finally
aftyer a few weeks, I replaced ttyS1 in the line above with cua1.
Everything started working! that leads to another question.  I read
these newsgroups often. I see may articles advising that we should not
use cua? in our setup because it is not standard. then why can't I get
ttyS? to work on my machine?

Another question:

Since cua1 works in the inittab, I just leave it there. If I start
minicom,
(as root or a regular user) I get permission denied /dev/modem. If I
instead try 'cu -l cua1' howver, I get the error permission denied, all
matching ports in use. This is of course bogus. I did a search and there
aren't any lock files out there. it makes no difference if I am root or
a regular user, I still get this message with cu.

Here's a look at cua1 permissions:

            crw--w--w-
when I change the permissions to  crw-rw-rw- cu works just fine!

I'm trying to understand what going on here, but I'm having a tough time
of it.
I doubt that the permissons for cua1 were incorrect, because I connect
to the net routinely using ppp. (run as root).

If you can give me a hand here, I appreciate it. I have ALL the howtos
and the network administators guide and I still can't figure this one
out. I'm trying to learn unix for my job and it's going pretty well.
this problem has me stumped though. Your experience and insight would be
appreciated.

Thanks,

--David

Lord grant me the serenity to accept the things I cannot change.The
courage
to change the things I can.And the wisdom to hide the bodies of the
people
          *I had to kill because they pissed me off*

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