[CentOS] How do I configure additional serial ports?

Mon Mar 12 18:41:27 UTC 2007
Alfred von Campe <alfred at 110.net>

On Mar 12, 2007, at 13:15, James Olin Oden wrote:

> As I understand it you can also set the kernel command line arg
> 8250.nr_uarts equal to some value like 8, 16, 32, etc, without having
> to rebuild your kernel (i.e. go into grub.conf and add to your kernel
> line " 8250.nr_uarts=32").

I tried this, but it didn't work.  I probably also need the  
CONFIG_SERIAL_8250_MANY_PORTS option enabled, and that probably can't  
be set on the kernel command line.

> IIRC, what you have to do is create a udev rule so that you can cause
> your serial port naming to persist the way you want.  I've never
> created one myself, but we have done that in my group where I work, so
> the problem is familiar to me.

I wrote a udev rule once (it was for setting permissions on a  
device), so I am somewhat familiar with this.  I'll see if I can  
write a rule that uses better names for the serial ports.

Alfred