Configuring Max_Luns - Red Hat ENTERPRISE LINUX 4 - ADMINISTRATION Manual

# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition.
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/VolGroup00/LogVol00
# initrd /initrd-version.img
#boot=/dev/hda
default=0
timeout=5
serial --unit=0 --speed=115200
terminal --timeout=5 serial console
title Red Hat Enterprise Linux Server (2.6.18-36.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-36.el5 ro root=/dev/VolGroup00/LogVol00
console=ttyS0,115200n8 acpi=off
initrd /initrd-2.6.18-36.el5.img
In this example, acpi=off has been appended to the kernel boot command line — the line starting
with "kernel /vmlinuz-2.6.18-36.el5".
Example 2.12. Kernel Boot Command Line with acpi=off Appended to It

2.4. Configuring max_luns

If RAID storage in your cluster presents multiple LUNs (Logical Unit Numbers), each cluster node must
be able to access those LUNs. To enable access to all LUNs presented, configure max_luns in the /
etc/modprobe.conf file of each node as follows:
1. Open /etc/modprobe.conf with a text editor.
2. Append the following line to /etc/modprobe.conf. Set N to the highest numbered LUN that is
presented by RAID storage.
options scsi_mod max_luns=N
For example, with the following line appended to the /etc/modprobe.conf file, a node can
access LUNs numbered as high as 255:
options scsi_mod max_luns=255
3. Save /etc/modprobe.conf.
4. Run mkinitrd to rebuild initrd for the currently running kernel as follows. Set the kernel
variable to the currently running kernel:
This means that
Configuring max_luns
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