atom feed3 messages in com.redhat.nahant-beta-listRe: really stupid question
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Jeff LaneOct 22, 2004 8:38 am 
Don MacAskillOct 22, 2004 3:59 pm 
Joshua JensenOct 22, 2004 4:05 pm 
Subject:Re: really stupid question
From:Don MacAskill (
Date:Oct 22, 2004 3:59:45 pm

I imagine it's similar to RHEL3, in that you can specify multiple consoles to have redirection on.

GRUB itself can only have one during it's menu phase, I think, but other than that, you can have multiple. Here's the relevant /boot/grub/menu.lst portions:

serial --unit=0 --speed=9600 terminal --timeout=2 serial console splashimage=(hd0,0)/grub/splash.xpm.gz title Red Hat Enterprise Linux WS (2.4.21-20.ELsmp) root (hd0,0) kernel /vmlinuz-2.4.21-20.ELsmp ro root=/dev/md1 console=ttyS0,9600 console=ttyS1,9600 console=tty0

(note that the 'kernel' line is all one line, mail is going to wrap it).

That'll pass grub menu control to the serial port 0, speed 9600. Once the kernel gets ahold of it, it should redirect console output to both serial ports and the standard tty0.

I believe the first one specified is the "primary" console which gets all the low-level kernel messages, and the other consoles do not, but I'm not 100% sure that's the case in all cases.

Hope that helps. I think there's info in the docs somewhere, which I imagine is where I got this info from originally, but I can't say exactly where for sure.

Oh, another interesting side note is that RHEL3's up2date process is intelligent enough to copy the serial console stuff from one kernel entry in GRUB to another when it's installing a new kernel. So you don't have to manually do this every time, just once. *Very* nice feature.


Joshua Jensen wrote:

I'd like to know this myself... I didn't think it was possible though.

On Fri, Oct 22, 2004 at 11:38:33AM -0400, Jeff Lane wrote:

Just a stupid question regarding the RHEL 4 installer...

How do I redirect the various TTYs outputs to the serial console??

I can pass console=ttyS1,38400 console=tty to the installer kernel and it will redirect the first console to serial so I can capture the kernel messages, but I also want to do this for the second tty to capture some commands run at the prompt, and also the 3rd and 4th console as well to get those messages...

Do I need to change the console=tty line to something like console=tty3 or is there some other trick???