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My notebook is Asus U31SD and I'm using Ubuntu 11.10 with gnome-shell and I'm having this weird problem that after login I can hear start sound and I barely see the desktop. To fix it I need to press every time Fn+F6 (more brightness).

I have tried to modify rc.local by adding

echo 0(or 10) > /sys/class/backlight/acpi_video0/brightness

Here is the rc.local file:

    #!/bin/sh -e
    # rc.local
    echo 0 > /sys/class/backlight/acpi_video0/brightness

but I don't know why it doesn't work. If i do an echo from terminal command is working.

Any help will be appreciated.

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The way you've written it, it sounds like you're literally writing "echo 0 > /sys/class/backlight/acpi_video0/brightness" to rc.local. Is this the case, or are you running this command from the command line? – Kris Harper Nov 1 '11 at 16:14
I have modified first post to include rc.local file. – Ionut Nov 1 '11 at 17:06

You should look at /var/log/boot.log to see if there's an error reported. It's probably not rc.local not working, but the script fails to work when rc.local is loaded.

At least it's what I encountered.

I added

chown ****(my username) /sys/kernel/debug/vgaswitcheroo/switch

echo OFF > /sys/kernel/debug/vgaswitcheroo/switch

to rc.local (and set rc.local to executable). And then I got

chown: cannot access `/sys/kernel/debug/vgaswitcheroo/switch': No such file or directory

in the boot.log, which seemed to indicate the script was run before the switching mechanism was set up.

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