Subject: Re: Serial Console Installs
To: Peter Eisch <>
From: Manuel Bouyer <>
List: port-i386
Date: 05/22/2007 21:22:17
On Tue, May 22, 2007 at 11:30:50AM -0500, Peter Eisch wrote:
> Is there a way to select to the iso bootloader on an install build to select
> the console for the install?
> I have a system (Dell 2650) with the console redirection config:
>   Console Redirection .............. Serial Port 1
>   Remote Terminal Type ............. VT100/VT220
>   Redirection After Boot ........... Disabled
> >From the serial console I never get to see the bootloader prompt.  If I
> change the Redirection After Boot Property to Enabled, I can see the
> bootloader but I lose console once the kernel starts initializing.
> If I use the DRAC/KVM on the console and catch the bootloader to issue:
>   consdev com0 
> I can continue with the serial console installation flawlessly.  It would be
> nice to eliminate the requirement of the KVM though.
> What is the method to build an install image using an alternative kernel
> named SINSTALL which is simply:
> -------------
> include "arch/i386/conf/INSTALL"
> options        CONSDEVNAME="\"com\"",CONADDR=0x3f8,CONSPEED=9600
> -------------
> This would get me two iso images that I could have available.

This would require some hacking in distrib/i386 to make use of the
alternate kernel.
I think it's easier to just create a bootfloppy-big-com, which is
bootfloppy-big with the bootblock configured to use the serial console.
See bootfloppy-com/Makefile to see what to add to bootfloppy-big/Makefile to
have a serial bootblock.

> Alternatively, is there an option to use for the bootloader to write and
> then read from all the devices it knows during the countdown?  If this were
> a flag or option that is used during install boots, it would be easily
> sufficient to handle all cases from one iso install image (with a little
> documentation).

This would be dangerous if e.g. you have something else connected to
the serial port, or if the serial port doens't exists.

> Perhaps all this changes after 3.x as I'm still using 3.1 code.  I've seen
> that there are changes with the 4.x release, does the bootloader use all
> interfaces there?

It's the same as in netbsd-3, but an iso image with console on com0 is
provided as well.

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference