Sunday, February 22, 2015

Fedora 21 : LCD screen backlight brightness on Acer Aspire 5742 issue

This is an update on the ongoing issue with a backlight in Fedora. I first experienced it in Fedora 15, although I suppose it is a much longer story.
Basically, backlight works, then update, stops working, then update works again, sometimes it needs a little tuning, sometimes not. Simply it is a problem Fedora (or upstream kernel) developers struggle for a very long time and cannot fix it. However, in Windows it works for years without a single issue.
I have a friend, who is a fantastic Linux expert and now I understand why he always says "Linux, on server absolutely yes, on workstation - no way." 

And he is the update for Fedora 21 on  Acer Aspire 5742.

acpi_backlight=vendor option does not work, even though it pretty much, nearly always was a good fix.
video.use_native_backlight=1 does not work at all.
pcie_aspm=force acpi_osi=Linux acpi_backlight=vendor partially works, it changes the brightness of the screen while using Fn keys, however the slider in Gnome settings and extension does not have effect at all.

Let's see what the next update will bring. ;-)

Friday, February 13, 2015

KVM : How to convert disk format

1. Remove the disk from the VM.

2. Convert the disk format, for example from raw to qcow2.

# qemu-img convert -p -O qcow2 FedoraWS.img FedoraWS.qcow2

3. Add a "new-format" disk to the VM.

Thursday, February 12, 2015

OpenSUSE 13.2 : How to install Revelation password manager.

1. Go to:

2. Select openSUSE 13.2.

3. Open with YaST, click OK.

4. Add repository, click Next.

5. Select revelation, click Next.

6. Click Next then OK and confirm root's password.

7. Install the following packages.

# zypper in python-pycrypto python3-pycrypto python-cracklib

8. Lunch Revelation.