[ILUG] Serial port access to a router

[Kenn Humborg]

On Mon, Nov 22, 1999 at 02:23:17AM -0000, subb3 at ibm.net wrote:
> 
> Hello
> 
> I am trying to connect to a Cisco router via console. The
> router and the linux box are connected via a serial cable.
> I have seyon but have never used it. What device name is the serial port on?
> I need to access this router and any help is appreciated.

You're working late!

The serial port is /dev/ttyS0 to /dev/ttyS3 (for DOS's COM1: to COM4:).
On a 2.0.x kernel you might need to use /dev/cua0 to /dev/cua3 instead.

Your cable probably needs to be a crossover (aka null-modem) cable.
A cable that you'd use to connect a PC to a modem is _not_ a crossover.

In a 25-way to 25-way (or 9-way to 9-way) crossover, pins 2 and 3 are
crossed over.  In a 25-way to 9-way crossover, pins 2 and 3 are connected
straight through.  A quick test with a multimeter will identify the
cable if there is any doubt.

Later,
Kenn