Question sent in by Michelle from New Jersey. (Repeat reader... YAY!)
Q: How can I disable ACPI on my CentOS servers?
A: You did not include why you would like to disable ACPI in your question, not that it is any of my business.
First, you can disable ACPI from the BIOS configuration screens. This is beyond the scope of this mini how to because there are just too many different BIOS versions out there.
In the past I had troubles with ACPI causing reboots of servers to fail. The machine would go down, but would hang in a powered on, but OS shut down state. I had to manually power off and then power on again from there to get the server back up. I found it was ACPI causing the reboot failures, so I did exactly what your asking and disabled ACPI.
NOTE: I first disabled ACPI in the BIOS, then proceeded...
Edit /etc/grub.conf and add acpi=off at the end of each kernel line.
Here is an example /etc/grub.conf file:
# 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. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/mapper/vg_srvone-lv_root
# initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux Server (2.6.32-431.20.5.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-431.20.5.el6.x86_64 ro root=/dev/mapper/vg_srvone-lv_root rd_LVM_LV=vg_srvone/lv_root rd_LVM_LV=vg_srvone/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet audit=1
initrd /initramfs-2.6.32-431.20.5.el6.x86_64.img
title Red Hat Enterprise Linux Server (2.6.32-431.20.3.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-431.20.3.el6.x86_64 ro root=/dev/mapper/vg_srvone-lv_root rd_LVM_LV=vg_srvone/lv_root rd_LVM_LV=vg_srvone/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet audit=1
initrd /initramfs-2.6.32-431.20.3.el6.x86_64.img
title Red Hat Enterprise Linux Server (2.6.32-358.11.1.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-358.11.1.el6.x86_64 ro root=/dev/mapper/vg_srvone-lv_root rd_LVM_LV=vg_srvone/lv_root rd_LVM_LV=vg_srvone/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet audit=1
initrd /initramfs-2.6.32-358.11.1.el6.x86_64.img
Here is the /etc/grub.conf file with acpi=off added to the end of each kernel line:
# 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. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/mapper/vg_srvone-lv_root
# initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux Server (2.6.32-431.20.5.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-431.20.5.el6.x86_64 ro root=/dev/mapper/vg_srvone-lv_root rd_LVM_LV=vg_srvone/lv_root rd_LVM_LV=vg_srvone/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet audit=1 acpi=off
initrd /initramfs-2.6.32-431.20.5.el6.x86_64.img
title Red Hat Enterprise Linux Server (2.6.32-431.20.3.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-431.20.3.el6.x86_64 ro root=/dev/mapper/vg_srvone-lv_root rd_LVM_LV=vg_srvone/lv_root rd_LVM_LV=vg_srvone/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet audit=1 acpi=off
initrd /initramfs-2.6.32-431.20.3.el6.x86_64.img
title Red Hat Enterprise Linux Server (2.6.32-358.11.1.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-358.11.1.el6.x86_64 ro root=/dev/mapper/vg_srvone-lv_root rd_LVM_LV=vg_srvone/lv_root rd_LVM_LV=vg_srvone/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet audit=1 acpi=off
initrd /initramfs-2.6.32-358.11.1.el6.x86_64.img
NOTE: The system will need to be rebooted in order to read the configuration from /etc/grub.conf