How do I activate power management or Advanced Power Management (APM) on my system?

Issue

Issues

1. How do I activate power management or Advanced Power Management (APM) on my system?

2. how can I check if apm is enabled or not from running os ?

3. How to disable it on Red Hat Enterprise Linux?

Environment

• All Red Hat Enterprise Linux

Resolution

How to enable :

• Advanced Power Management features (APM) can be activated on your system by starting the APM daemon (apmd). To start this immediately, use the service command:

  service apmd start
  

• To ensure that this daemon is enabled across reboots, use the chkconfig command:

  chkconfig apmd on
  

Note: In order to execute these commands, user has to be the root user.

How to check whether it has enabled :

#dmidecode | grep -i apm

#service apmd status
#/etc/init.d/apmd status
#ps aux | grep apmd
#pstree -paul| grep apmd 

Note :

How to disable it :

 
As an example it will look like :

---------
default=1
timeout=7
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux AS (2.4.21-20.EL)
        root (hd0,0)
        kernel /vmlinuz-2.4.21-20.EL ro root=LABEL=/ apm=off
        initrd /initrd-2.4.21-20.EL.img
title Red Hat Enterprise Linux AS (2.4.21-20.ELsmp)
        root (hd0,0)
        kernel /vmlinuz-2.4.21-20.ELsmp ro root=LABEL=/ apm=off
        initrd /initrd-2.4.21-20.ELsmp.img
---------

• And on that same machine you also need to disable the apmd daemon at the chkconfig service like :

#chkconfig apmd off
#service apmd stop