HP Integrated Lights-Out 2 User Guide

After the server completes POST, the server system ROM transfers control to the operating system
boot loader. If you are using Linux, you can configure the operating system boot loader to interact
with the server serial port instead of the keyboard, mouse, and VGA console. This configuration
enables you to view and interact with the operating system boot sequence through the Remote
Serial console. For an example of a Linux operating system boot loader, see “Linux configuration
example” (page 101).
After the operating system boot loader completes, the operating system continues to load. If you
are using a Linux operating system, you can configure the operating system to provide a login
session to the system through the serial port, enabling the Remote Serial Console to prompt you
for the system user login ID and password. Using this configuration enables you to interact with
the operating system as an operating system user or as a system administrator.
Although additional configuration steps are required to use Remote Serial Console (as compared
to using the remote console or IRC), the Remote Serial Console allows Telnet or SSH users to interact
with the server remotely and without requiring an iLO 2 Advanced license and is the only way a
true text-based remote console is presented by iLO 2.
Linux configuration example
The boot loader is the application that loads from the bootable device when the server system
ROM finishes POST. For Linux operating systems, the boot loader that is usually used is GRUB. To
configure GRUB to use the Remote Serial Console, modify the GRUB configuration file to look like
the following (Red Hat Linux 7.2 sample shown):
serial -unit=0 -speed=115200
terminal -timeout=10 serial console
default=0
timeout=10
#splashimage=(hd0,2) /grub/splash.zpm.gz
title Red Hat Linux (2.4.18-4smp)
root (hd0,2)
kernel /vmlinuz-2.4.18-4smp ro root=/dev/sda9 console=tty0 console=ttyS0,115200
initrd /initrd-2.4.18-rsmp.img
After Linux is fully booted, a login console can be redirected to the serial port. The /dev/ttyS0
and /dev/ttyS1 devices, if configured, enable you to obtain serial tty sessions through the
Remote Serial Console. To begin a shell session on a configured serial port, add the following line
to the /etc/inittab file to start the login process automatically during system boot (this example
invokes the login console on /dev/ttyS0):
Sx:2345:respawn:/sbin/agetty 115200 ttyS0 vt100
For more information about configuring Linux for use with the Remote Serial Console, see the
technical publication Integrated Lights-Out Virtual Serial Port configuration and operation HOWTO
on the HP website at http://www.hp.com/servers/lights-out.
Virtual Serial Port enhancements
iLO 2 firmware 1.35 implements a dynamic flag that instantly informs the server system ROM of
an iLO 2 Remote Serial Console connection. After the system ROM POST code recognizes the
Remote Serial Console connection, the system begins redirecting the console input and output to
the server serial port and the Remote Serial Console. You can establish a Remote Serial Console
session at any time before or during the system POST sequence, and you can view and modify
the POST. After disconnecting the Remote Serial Console session, the iLO 2 firmware resets the
dynamic flag to inform the server system ROM that the session is no longer active. Then, the server
system ROM cancels the redirection to the server serial port.
The system ROM RBSU setup must be configured to use iLO 2 Virtual Serial Port for this enhancement
to be operational. For more information, see “Configuring Remote Serial Console” (page 100).
iLO 2 Remote Console 101