Re: serial console device, and installboot vs. /boot.cfg

On Fri, Feb 09, 2024 at 08:16:53AM -0500, Greg Troxel wrote:
> Steve Rikli <[email protected]> writes:
> 
> > Well, what I really want :-) is to be able to switch between a COM serial
> > port and a Pc keyboard without re-configuring NetBSD, and that's what I
> > was hoping for with auto.
> >
> > "auto" activates the serial console in my config, but the Pc keyboard+VGA
> > sees no boot messages or menus, which feels like "auto" and "com0" are
> > effectively the same in my setup. More experiments warranted.
> 
> I think what you want is "dual" not "auto", to use both com0 and vga, to
> output to both, and to read from either.  I have no reason to think
> there is any code to do this.

Yes, I expect that's right.

My FreeBSD systems use "-D" in /boot.config, from their boot(8)

   -D    boot with the dual console configuration.  In the
         single configuration, the console will be either
         the internal display or the serial port, depending
         on the state of the -h option below.  In the dual
         console configuration, both the internal display
         and the serial port will become the console at the
         same time, regardless of the state of the -h

I was hoping for a similar configuration with my NetBSD PCs, but what
I've got now (primary serial console) is sufficiently functional for me.

I'm still at somewhat of a loss to understand why "auto" and "com0" are
behaving the same in my setup with serial boot blocks, with both COM
port and keyboard connected.

Perhaps the presence of "speed=" option signals to the "console=auto"
option that the serial port should in fact be used. Merely speculating.

Thanks,
sr.