Support Notes for Red Hat Enterprise Linux AS v.5.7 for HP Integrity Servers

1. Select the Boot Configuration option then press ENTER to display the Boot
Configuration menu.
2. Select Console Configuration then press ENTER to select it.
3. Select the VGA entry then press P.
4. Press ESC to return to the previous menu.
5. Press Y to save the new console setting.
— If the device is a serial device such as a terminal emulator, then set (or confirm) the
firmware setting for the primary console to Serial as follows:
1. Select the Boot Configuration option then press ENTER to display the Boot
Configuration menu.
2. Select Console Configuration then press ENTER to select it.
3. Select the Serial entry then press P.
4. Press ESC to return to the previous menu.
5. Press Y to save the new console setting.
6. Exit from the EFI Boot Manager to the Linux boot prompt then enter:
ELILO Boot: console=ttyS0
• Use of a serial console when a VGA card is present
If the Red Hat kernel detects a VGA card, it defaults to using the VGA display as system
console.
To use serial console, use the EFI Boot Manager to select the serial device as the primary (or
only) console device as described in the previous issue.
• Applications may hang when opening Management Processor UART
The Management Processor UART on all HP Integrity servers running RHEL do not supply the
carrier detect signal. This causes applications to hang when opening the UART device because
no carrier detect is sent unless the O_NDELAY or O_NONBLOCK flag is set.
For example, the command echo foo > /dev/ttyS0 would hang.
Typically, this is not a problem because /dev/ttyS0 is usually used as a console, the agetty
process opens it with O_NONBLOCK, and processes spawned by agetty generally inherit
the already-opened device. However, there are some cases where the device must be opened
again so applications will observe the hang.
Use the following procedure to resolve the problem:
1. Add the -L option to the agetty line in the /etc/inittab file as follows:
co:2345:respawn:/sbin/agetty -L ttyS0 9600 vt100-nav
2. Signal the init process to re-read the inittab file with the following command:
kill -HUP 1
3. If you are logged in to the console, exit then log in again to restart the agetty process.
• Using integrated Lights Out remote console during installation may cause firstboot program
to fail
When using the HP Integrity Integrated Lights-Out remote console during a RHEL 5.x installation,
the firstboot program that runs during the installation may generate large amounts of
output and fail though the installation completes. After installation, the firstboot program
can be rerun, as root, and does not create any display problems.
16 Recommendations, Limitations, and Known Issues