Troubleshooting - Novell LINUX ENTERPRISE SERVER 11 - ADMINISTRATION Administration Manual

down. To avoid this, a special kernel extension has been developed for mobile devices.
See /usr/src/linux/Documentation/laptop-mode.txt for details.
Another important factor is the way active programs behave. For example, good editors
regularly write hidden backups of the currently modified file to the hard disk, causing
the disk to wake up. Features like this can be disabled at the expense of data integrity.
In this connection, the mail daemon postfix makes use of the variable
POSTFIX_LAPTOP. If this variable is set to yes, postfix accesses the hard disk far
less frequently.
In SUSE Linux Enterprise Server these technologies are controlled by
laptop-mode-tools.

15.4 Troubleshooting

All error messages and alerts are logged in the file /var/log/messages. If you
cannot find the needed information, increase the verbosity of the messages of powersave
using DEBUG in the file /etc/sysconfig/powersave/common. Increase the
value of the variable to 7 or even 15 and restart the daemon. The more detailed error
messages in /var/log/messages should help you to find the error. The following
sections cover the most common problems with powersave and the different sleep
modes.
15.4.1 ACPI Activated with Hardware
Support but Functions Do Not Work
If you experience problems with ACPI, use the command dmesg|grep -i acpi
to search the output of dmesg for ACPI-specific messages. A BIOS update may be
required to resolve the problem. Go to the home page of your laptop manufacturer, look
for an updated BIOS version, and install it. Ask the manufacturer to comply with the
latest ACPI specification. If the errors persist after the BIOS update, proceed as follows
to replace the faulty DSDT table in your BIOS with an updated DSDT:
1 Download the DSDT for your system from
http://acpi.sourceforge
.net/dsdt/index.php. Check if the file is decompressed and compiled as
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