How do I redirect the kernel console output on Ubuntu 10.04

Question

When I reboot my Ubuntu 10.04 nodes, I'd like to be able to see the kernel boot messages when connecting to the IPMI interfaces using Serial Over LAN mode (ttyS0). What do I need to do to be able to redirect these messages to ttyS0?

Ideally, I'd like them to also still appear in the usual place (tty0, I think) for when I plug a monitor directly into the box.

Solution 1

After doing some research, apparently you need to edit the /etc/default/grub file and add the following line:

GRUB_CMDLINE_LINUX="console=tty0 console=ttyS0"

Then run the update-grub command which will update /boot/grub/grub.cfg accordingly.

Solution 2

It has been a long time since I did this but this might work.

Edit /etc/grub.conf and add the following to your kernel line

console=tty0 console=ttyS0

If that does not work you might need to make a special boot option for just serial and put the ttyS0 first and use the example as your monitor boot option

Comments

[Lorin Hochstein]

I think the grub stuff is in a different place in ubuntu, there's no /etc/grub.conf file.

[Mike]

chances are its in /etc/grub/grub.conf then

[Matthew Iselin]

/boot/grub on Ubuntu