Using Redhat and grub.

Is there a way to send the init text/messages to both the serial port
AND a CRT console while a system boots up?

ie: kernel /boot/vmlinuz-2.4.20-30.7smp ro root=/dev/hda1 console=tty0,
console=ttyS0,38400 -- will only display init related messages (the
"OK" text) on the serial port, nothing shows on the CRT. If I reverse
the console options in the line above, all text goes only to the CRT.

I want to avoid adding two different configurations in grub (to choose
between serial or CRT consoles). All the post/articles I've read so far
only refer to using one or the other as the "primary" console. I'd like
to have two primary's.


Reason I ask: If the system stops during boot-up, waiting for a fsck of
a filesystem, and your only looking at a plugged in CRT monitor, you'll
never see a login: prompt.


Thanks,
Paul

On Wed, 20 Apr 2005 17:05:44 -0500, Paul Tader
<netnews@linuxscope.com> wrote:
> Using Redhat and grub.
>
> Is there a way to send the init text/messages to both the serial port
> AND a CRT console while a system boots up?
>
> ie: kernel /boot/vmlinuz-2.4.20-30.7smp ro root=/dev/hda1 console=tty0,
> console=ttyS0,38400 -- will only display init related messages (the
> "OK" text) on the serial port, nothing shows on the CRT. If I reverse
> the console options in the line above, all text goes only to the CRT.
>
What is on the other end of the serial port? Can't you plug a crt into
that, perhaps using a kvm switch?



--
"I deleted a file from my PC last week and I have just realized that I
need it. If I turn my system clock back two weeks will I have my file
back again?"

Bill Marcum wrote:
> On Wed, 20 Apr 2005 17:05:44 -0500, Paul Tader
> <netnews@linuxscope.com> wrote:
>
>>Using Redhat and grub.
>>
>>Is there a way to send the init text/messages to both the serial port
>>AND a CRT console while a system boots up?
>>
>>ie: kernel /boot/vmlinuz-2.4.20-30.7smp ro root=/dev/hda1 console=tty0,
>>console=ttyS0,38400 -- will only display init related messages (the
>>"OK" text) on the serial port, nothing shows on the CRT. If I reverse
>>the console options in the line above, all text goes only to the CRT.
>>
>
> What is on the other end of the serial port? Can't you plug a crt into
> that, perhaps using a kvm switch?
>
>
>
There is a Cyclades on the end of the serial port. That's normally what
we work with, but the occasion arises when where right next to the
system, with a monitor/keyboard, and we want to troubleshoot it from
there.

For instance, I've got a CRT/keyboard hooked up to a system, I rebooted
it and never get a login prompt. Why? because it paused waiting for a
fsck on a filesystem. I'd never know that until I went back to a serial
console because the prompts don't show on the CRT.

Paul

On Wed, 20 Apr 2005 17:05:44 -0500 Paul Tader <netnews@linuxscope.com> wrote:

| Using Redhat and grub.

Sorry to hear that.


| Is there a way to send the init text/messages to both the serial port
| AND a CRT console while a system boots up?

This would be nice. I'd like to see it at the kernel boot time, too.


| ie: kernel /boot/vmlinuz-2.4.20-30.7smp ro root=/dev/hda1 console=tty0,
| console=ttyS0,38400 -- will only display init related messages (the
| "OK" text) on the serial port, nothing shows on the CRT. If I reverse
| the console options in the line above, all text goes only to the CRT.

That would be a nice feature to make it so a "general device" is actually
duplicated across multiple real devices in a sane way.

While we are at it, how about accepting keyboard input from any of them,
including USB keyboards as well as PS/2 and other keyboard sources, in
addition to the serial port.

Why not 2 or more serial ports, too?


| I want to avoid adding two different configurations in grub (to choose
| between serial or CRT consoles). All the post/articles I've read so far
| only refer to using one or the other as the "primary" console. I'd like
| to have two primary's.

Makes sense to me. I still have fond memory of Sun workstations.


| Reason I ask: If the system stops during boot-up, waiting for a fsck of
| a filesystem, and your only looking at a plugged in CRT monitor, you'll
| never see a login: prompt.

If init hasn't started logins, yet, why would the serial port be any
different? And logins might not work anyway, until the fsck is done.

--
-----------------------------------------------------------------------------
| Phil Howard KA9WGN | http://linuxhomepage.com/ http://ham.org/ |
| (first name) at ipal.net | http://phil.ipal.org/ http://ka9wgn.ham.org/ |
-----------------------------------------------------------------------------

On Thu, 21 Apr 2005 14:20:09 -0500 Paul Tader <netnews@linuxscope.com> wrote:
| Bill Marcum wrote:
|> On Wed, 20 Apr 2005 17:05:44 -0500, Paul Tader
|> <netnews@linuxscope.com> wrote:
|>
|>>Using Redhat and grub.
|>>
|>>Is there a way to send the init text/messages to both the serial port
|>>AND a CRT console while a system boots up?
|>>
|>>ie: kernel /boot/vmlinuz-2.4.20-30.7smp ro root=/dev/hda1 console=tty0,
|>>console=ttyS0,38400 -- will only display init related messages (the
|>>"OK" text) on the serial port, nothing shows on the CRT. If I reverse
|>>the console options in the line above, all text goes only to the CRT.
|>>
|>
|> What is on the other end of the serial port? Can't you plug a crt into
|> that, perhaps using a kvm switch?
|>
|>
|>
| There is a Cyclades on the end of the serial port. That's normally what
| we work with, but the occasion arises when where right next to the
| system, with a monitor/keyboard, and we want to troubleshoot it from
| there.
|
| For instance, I've got a CRT/keyboard hooked up to a system, I rebooted
| it and never get a login prompt. Why? because it paused waiting for a
| fsck on a filesystem. I'd never know that until I went back to a serial
| console because the prompts don't show on the CRT.

So basically you see nothing. The logins are waiting for fsck but you
don't see the messages so you don't know an fsck is happening or why,
and you just wonder where the login prompt is that is supposed to show
up (though without any init messages). At least if you had output going
both ways, you could see that it was an fsck and wait without wondering.

A multi-interface /dev/console would be nice.

--
-----------------------------------------------------------------------------
| Phil Howard KA9WGN | http://linuxhomepage.com/ http://ham.org/ |
| (first name) at ipal.net | http://phil.ipal.org/ http://ka9wgn.ham.org/ |
-----------------------------------------------------------------------------

Paul Tader wrote:
> Using Redhat and grub.
>
> Is there a way to send the init text/messages to both the serial port
> AND a CRT console while a system boots up?
>
> ie: kernel /boot/vmlinuz-2.4.20-30.7smp ro root=/dev/hda1 console=tty0,
> console=ttyS0,38400 -- will only display init related messages (the

Looks fine except for the extra "," did you mean:
console=tty0 console=ttyS0,38400

"Chris Cox" <ccox_nopenotthis@airmail.net> wrote in message
news:116i9v2r2o9kt50@corp.supernews.com...
> Paul Tader wrote:
>> Using Redhat and grub.
>>
>> Is there a way to send the init text/messages to both the serial port
>> AND a CRT console while a system boots up?
>>
>> ie: kernel /boot/vmlinuz-2.4.20-30.7smp ro root=/dev/hda1 console=tty0,
>> console=ttyS0,38400 -- will only display init related messages (the
>
> Looks fine except for the extra "," did you mean:
> console=tty0 console=ttyS0,38400

According to the engineer I was discussing exactly this with last week, no.
The usual fix is to put in two entries in lilo.conf or grub.conf and select
one or the other depending on which display you want.

I haven't verified this myself.