Reset Stalled, Non-Responsive Linux system

At times even a Linux box might stall or become non-responsive, not even giving you an option to open a terminal screen. In that case, you can use one of the following 2 options to restart your system.

1. [Riding Shiny Elephants Is Not Utterly Boring]-Method.

Alt-key + PrtSc-key + r

Alt-key + PrtSc-key + s

Alt-key + PrtSc-key + e

Ubuntu 11.10 / 12.04 & Realtek network card RTL8111/RTL8168B driver installation

My HP Pavilion dv7-6190ed uses a Realtek Lan adapter (RTL8111/RTL8168B PCI Express Gigabit), known to cause trouble with Ubuntu 11.10 & 12.04  (automatically installs RTL8169 drivers)

The default RTL8169 driver seems to work at first, but keeps loosing connection, and has high packet losses. *Not very useful.

Solution:

Install the correct driver (from the manufacturer)

Switch off ATI VGA in Hybrid cards with Intel on Ubuntu (solving overheating)

On my HP Pavilion dv7-6190ed (FW F.18) I have an AMD Radeon HD 6700M series video card, which sometimes it make my laptop overheat until 97 C.
The ATI Radeon and Intel VGA both run, and seem to go rogue at times. At the time of my install, (around Jan. 2012) the Catalyst drivers seem to have a problem with Ubuntu 11.10 (oneiric).
By switch off VGA AMD Radeon part of the card, it seem to decrease the running temperature, to about 60 C on av. Along with that it runs way more quiet. (no cooling fans going ballistic)
So basically, turning off the ATI VGA part of the card will decrease the heat problem in Ubuntu.

NOTE:  Since posting this workaround, there has been an upgrade for the BIOS (FW F.1B). They fixed option available now for ATI, may reduce heat too. so try upgrading the BIOS FIRST !!. here is the link>> BIOS FW F.18)

Remove Old Kernel versions, and update your grub Menu

If you want to clean up your system, and free some space on your system partiton, removing old unused kernel versions is a good start.

NOTE: Before starting any of this, make sure you have a solid back-up (There are several good GUI driven back-up systems for Linux available, although I still like to run my own scripts using rsync)

1. find out what the current kernel version is (open a Terminal screen): 

uname -r

2. Do a test run and see what will be removed. (nothing will actually be removed. it is so called a dry - run command)

Recover SD Card data in Linux

Deleted your family pictures on your camera by mistake?

You can recover them with the following procedure in Linux, (command line) given they weren't overwritten already.

Preemptive: You need to install gddrescue & testdisk

Sudo apt-get install gddrescue testdisk

1. find out to what device the SD card is loaded and where it is mounted.

Run in terminal screen (command line)

Video Editing in Blender 2.49b & 2.52alfa2 using ogv input files

In the past when on Hardy Heron (Ubuntu 8.04Lts) and Blender 2.45, you could use the ogg/ogv files created by "RecordMyDesktop" and process them as pleased.

upgraded to Lucid (Ubuntu 10.4Lts) that by default comes with Blender 2.49b in the repositories, You can't use ogv files in blender VSE. (created by "RecordMyDestop").

But there is a workaround:

Blender 2.49b: No Audio in VSE with Ubuntu 10.4 LTS (Lucid)

Setup:

Ubuntu 10.4 LTS
Blender 2.49b (from distribution or blender.org)

Issue:

Audio files in the Video Editor Sequencer, can't be played.

Solution:

Open Terminal screen,and type: 

sudo gedit  /etc/environment  

Add at the end of the file the following line: 

SDL_AUDIODRIVER=pulse

Save the file and restart computer.

Ubuntu 9.10/10.4: No Audio on HP Pavilion dv7-3128ca

Installing Ubuntu 9.10 - Karmic or 10.01 - Lucid on a HP Pavilion Entertainment Pc: dv7 series. (dv7-3128ca) needs extra settings for the audio (including Mic-In) to work.

Add to /etc/modprobe.d/alsa-base.conf the following lines

options snd-hda-intel model=dell-m4-2
options snd-hda-intel enable_msi=1
options snd-hda-intel model=hp-dv5

(set settings in profile to analog stereo duplex )

Ubuntu 9.10: No audio on IBM ThinkPad T40 (Karmic-Koala)

After Installing Karmic - Koala (Ubuntu 9.10) on an old IBM thinkpad T40, there was no audio.

Adding a module seem to solve the problem.

/etc/modprobe.d/alsa-base.conf

Open a Terminal screen and type: gksudo gedit /etc/modprobe.d/alsa-base.conf Add the flollowing line at the Bottom, save and Reboot. options snd-hda-intel model=ibm-thinkpad

Enjoy your sound at next boot.

Ubuntu 9.10: No audio on Acer-Aspire-8920G (Karmic-Koala)

Installing Karmic - Koala (Ubuntu 9.10) on Acer-Aspire-8920(G):

Out of the box, you won't have Audio.

Adding a module seem to solve the problem.

/etc/modprobe.d/alsa-base.conf

Open a Terminal screen and type: Sudo gedit /etc/modprobe.d/alsa-base.conf Add the flollowing line at the Bottom, save and Reboot. options snd-hda-intel model=auto

Enjoy your sound at next boot.

Creating Thumbnails on Command Line

Image Magick is a great free image processing tool to do batch conversions. Many hosting companies running Linux servers will offer it by default. It will empower your website to create thumbnails and rescale images on the go (given your web-code utilizes it). For a full description click here

In this posting we want to explain how to create thumbnails (one by one or in batch)

Archive E-mails in Evolution (Ubuntu 8.04/9.04)

Intro:
One thing I really liked in MS-Outlook, was the Archive option; creating one file with the complete sub-folder structure preserved. Evolution does not yet have this feature, however, you can mimic it, with a very similar result.
I have switched from Outlook to Evolution around July 2008, And we are currently March 2009. So far, I haven't archived anything, and my daily Back-up starts to take way more time than I'm willing to bare.

Goal:
I want to outline a procedure, that will give me a system very much like the outlook archives. I used to Archive Quarterly.

Procedure:
I Prefer to work in my Virtual Box, to make sure I won't mess up anything in my real time version. (work off-line.)

Mass-change of Directory/File permissions @ command line.

A Quick note on how to change permissions of a whole directory structure and/or all containing files.

1. Changing permissions of Files in a directory structure, (starting point is current directory)(Example: set all files to 644)
   
   Sudo find . -type f -exec chmod 644 {} \;
   
2. Changing permissions recursively of all directories from current directory as starting point. (Example: set directories to 755)
   Sudo find . -type d -exec chmod 755 {} \;

Ubuntu 8.04: Screen Brightness Control for Acer Aspire 8920G

The FN-key + left and right arrow is used to change screen brightness. By default this doesn't work. Here is how to make them work. (I found this code in several help forums and modified it to make it work for my Acer).

Step1:

Before you start, make a backup of these files (video_brightnessup.sh and video_brightness_down.sh) so you can put things back the way they were if necessary.

Installing Windows XP/Vista true type fonts in Ubuntu 8.04/9.04 system wide

First find out in which location Linux has installed the True Type fonts. It is usually at the location '/usr/share/fonts/truetype/' . But you may also do a search for the same as follows:

# locate .ttf -b

Ubuntu 8.04: BlueTooth headset in Skype on Acer Aspire 8920G

Normally the installation of Ubuntu should detect the BT-controller. Turn on the BT receiver/transmitter and you will see if it is detected. Go in terminal mode:

Test if the BT adapter is working:

$ hciconfig -a

If you get an output with hci0 and manufactures name, the BT adapter is working.

Config BT configuration file:

$ sudo gedit /etc/bluetooth/hcid.conf

Near the top of the file you will see the following:

# HCId options options { # Automatically initialize new devices autoinit yes; # Security Manager mode # none - Security manager disabled # auto - Use local PIN for incoming connections # user - Always ask user for a PIN # security user;

Change the security user line to

security auto A

few lines down from this is a section about password:

# Default PIN code for incoming connections passkey "1234";

Change the default password “1234” to something else, e.g.: 8372.


This will be the passkey required for other Blue tooth devices to connect to you and it would be insecure to leave it at the default. SAVE the file and EXIT.

Restart the BT service to activate the changes in the config-file above.

$ sudo /etc/init.d/bluetooth restart

An informational box will appear in your task bar saying:


-0 Device has been made discoverable


where is your computer's name.
In my case Aspire9820: "Aspire8920-0 Device has been made connectable".

Turn on BT headset , but don't go into pairing mode, and type the following:

$ hcitool scan

your BT adapter will scan for devices and show your headset. Occasionally it won't show anything, in which case you can try the scan while having te headset in pairing mode (Your headset probably has been paired with another device, putting it in pairing mode wile scanning again, will make it visual)


The output would look like this:

$ hcitool scan

Scanning ...
00:41:2E:AA:CB:C1 PLANTRONICS
$


Take note of the MAC-address, you will need it in next section.

Create a new (hidden) file in your home directory called “. asoundrc”

sudo gedit ~/.asoundrc

Add the following code and add the Substitute the MAC-address with your MAC-address that you gathered as seen earlier.

pcm.bluetooth { type bluetooth device 00:41:2E:AA:CB:C1 profile "auto }

Save and Exit the editor

Loading modules and making pulse audio (default for Skype) aware of the BT device.

$ sudo hciconfig hci0 voice 0x0060

$ sudo modprobe snd_bt_sco

$ sudo modprobe sco

If you would like to load the drivers automatically on each boot, only add the two modprobe lines above to the end of the /etc/modules file (sudo gedit /etc/modules)

$ pactl load-module module-alsa-sink device=bluetooth

$ pactl load-module module-alsa-source device=bluetooth

If you do kernel updates or system updates to sound drivers, you might have to run these last 2 commands again to make your headset work with Skype. (I would suggest to keep them in a file on your desktop and make them executable for higher convenience. Alternatively you could create another hidden file in your home folder, but you might have side effects with it and not recommendable.

NOTE:

This procedure is to make your headset work with Skype, not to play your audio. Your BT device is not yet connected to your sound card yet. If you choose to create that functionality you will have to add few more procedures. (not covered in this manual)

Ubuntu 8.04: USB Devices in Guest O/S with Virtual Box

Once Virtual box is installed and working, you might find USB devices unrecognized or giving Error about no permission in usbfs ...

The Solution for this issue:

Check if the group id for vboxusers: (should have been created as part of installing Vbox.)

$ more /etc/group | grep vboxusers

result: vboxusers:x:124:username (where username is your username)

Ubuntu 8.04 LTS: Acer Aspire 8920(G) LAN/WAN configuration.

Wireless:

The wire-less works out of the box. You only need to configure your security (WEP / WPA)

Wired:

Aspire 8920 uses an Attansic Technology Corp Atheros AR8121 / AR8113 PCI-E card. Unfortunatley that hasn't been included in the current kernels. Therefore you need to do this manually. The following forum has a good description (http://ubuntuforums.org/showthread.php?t=770173) In short here:

• Install build-essential (synaptic, aptitude or apt-get)
• download the linux driver from: http://support.asus.com/download/dow...model=P5KPL-CM or : http://www.bas-r.nl/atheros_lan_driver/ (this has the latest, needed for 2.6.24-24-generic)
• Unpack in your Home directory ex. /home/user//LinuxDrivers/L1e_Lan/l1e-l2e-linux-v1.0.0.4/src
• in this directory run: sudo KBUILD_NOPEDANTIC=1 make sudo KBUILD_NOPEDANTIC=1 make install
• This will install driver in /lib/modules/2.6.24-22-generic/kernel/drivers/net/atl1e/at1le.ko
• in this directory run: sudo insmod ./atl1e.ko

Ubuntu 8.04/9.04: NVidia Geforce Restricted Drivers Installation (Aspire 8920G)

Nvidia Restricted driver installation.

I've used this procedure on different versions of Ubuntu. (8.04 / 8.10 / 9.04) and for different Nvidia Geforce cards (6600, 7300, 9500, ... ) and for all it is the same method. Just make sure you download the correct driver for your card.

1. Before you start, backup your current xorg.conf file: sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.backup1
   
   
2. Download the latest drivers for your version of Linux here: http://www.nvidia.com/object/unix.html (pick the right version and processor type)
   
   
3. Open terminal screen
   
   
4. Become root: sudo su
   
   
5. kill the x server with: killall gdm (in case you run gnome desktop) ore use: kill -9 PID#
   
   
6. Check with ps aux | grep gdm if all instances are really killed.
   
   
7. make the downloaded file executable: chmod +x /your_download_location/NVIDIA-Linux-x86-180.17-pkg1.run
   
   
8. Run the file: sh NVIDIA-Linux-x86-180.17-pkg1.run If all is right and X indeed has been killed the program will do it's thing. You will have to recompile the driver. At the end you will be asked to configure xorg.conf. Go ahead and do that.
   
   
9. Reboot or Restart X (reboot is the easiest just type reboot as root)
   
   
10. When the system is rebooted; open terminal screen again. and type: sudo nvidia-settings Don't run the Nvidia settings from the menu, unless you have changed the menu item to run it as root. you need those permissions to write back the new settings you pick into your xorg.conf file.
    
    
11. Select the settings you want (even dual screen) and save to xorg.conf

This should get you the beautiful 1920 x 1080 resolution the Acer Aspire 8920G delivers.

Hint, if you want to use dual screens, Twin view is an option but I would suggest to go for separate X screens. This has some disadvantages but allows you to run your laptop either in dual screen mode or single screen boot without to change the xorg.conf file. the machine is powerful enough to handle 2 X screens.

I suggest you to copy the new xorg.conf to a new backup file again.

NOTE:

Every time you update the kernel you will have to redo this process as the driver has been compiled in the current kernel manually.

If you have done many modifications to your xorg.conf file, I would suggest to copy it to a master file for later use. you can just copy that one back to xorg.conf after re-installing the Nvidia drivers. (saves you from doing all the settings again)

I attach my xorg.conf for Acer Aspire 8920G in Dual Screen mode as example (2 x screens: 1280x1024 external monitor and 1920x1080 laptop screen)

File: /etc/X11/xorg.conf

# nvidia-settings: X configuration file generated by nvidia-settings # nvidia-settings: version 1.0 (buildmeister@builder57) Sun Dec 14 20:59:56 PST 2008 # nvidia-xconfig: X configuration file generated by nvidia-xconfig # nvidia-xconfig: version 1.0 (buildmeister@builder57) Sun Dec 14 20:59:00 PST 2008 Section "ServerLayout" Identifier     "Layout0" Screen      0 "Screen0" 1280 0 Screen      1 "Screen1" LeftOf "Screen0" InputDevice    "Keyboard0" "CoreKeyboard" InputDevice    "Mouse0" "CorePointer" EndSection Section "Files" EndSection Section "Module" Load           "dbe" Load           "extmod" Load           "type1" Load           "freetype" Load           "glx" EndSection Section "ServerFlags" Option         "Xinerama" "0" EndSection Section "InputDevice" # generated from default Identifier     "Mouse0" Driver         "mouse" Option         "Protocol" "auto" Option         "Device" "/dev/psaux" Option         "Emulate3Buttons" "no" Option         "ZAxisMapping" "4 5" EndSection Section "InputDevice" # generated from default Identifier     "Keyboard0" Driver         "kbd" EndSection Section "Monitor" Identifier     "Monitor0" VendorName     "Unknown" ModelName      "Seiko" HorizSync       30.0 - 75.0 VertRefresh     60.0 Option         "DPMS" EndSection Section "Monitor" Identifier     "Monitor1" VendorName     "Unknown" ModelName      "Philips 170S" HorizSync       30.0 - 83.0 VertRefresh     56.0 - 76.0 EndSection Section "Device" Identifier     "Device0" Driver         "nvidia" VendorName     "NVIDIA Corporation" BoardName      "GeForce 9500M GS" BusID          "PCI:1:0:0" Screen          0 EndSection Section "Device" Identifier     "Device1" Driver         "nvidia" VendorName     "NVIDIA Corporation" BoardName      "GeForce 9500M GS" BusID          "PCI:1:0:0" Screen          1 EndSection Section "Screen" Identifier     "Screen0" Device         "Device0" Monitor        "Monitor0" DefaultDepth    24 Option         "TwinView" "0" Option         "metamodes" "DFP: 1920x1080_60 +0+0" SubSection     "Display" Depth       24 EndSubSection EndSection Section "Screen" # Removed Option "metamodes" "CRT: nvidia-auto-select +0+0" Identifier     "Screen1" Device         "Device1" Monitor        "Monitor1" DefaultDepth    24 Option         "TwinView" "0" Option         "TwinViewXineramaInfoOrder" "CRT-0" Option         "metamodes" "CRT: 1280x1024_75 +0+0; CRT: nvidia-auto-select +0+0" SubSection     "Display" Depth       24 EndSubSection EndSection

Ubuntu 8.04: Sound Card Setup for Acer Aspire 8920G

Sound Card set-up

There is at the moment of this writing a new project running to create scripts that install the ALSA drivers (by soundcheck). The Ubuntu forums host the discussions here: http://ubuntuforums.org/showthread.php?t=962695 I've tried this but it didn't work (known issues with kernel version, and unfortunately the workaround didn't work either) So back to the trick from while ago with updated source code.

1. Set model to acer-aspire in /etc/modprobe.d/alsa-basegksudo gedit /etc/modprobe.d/alsa-base (add the following line at bottom) options snd-hda-intel model=acer-aspire
2. Download and compile hda-verb-0.3.tar.gz from: ftp://ftp.suse.com/pub/people/tiwai/misc/ unpack the file and then compile the code with the make command.
3. Copy the compiled program to /usr/local/bin (sudo cp hda-verb /usr/local/bin/)
4. Add the following line to /etc/rc.local (before exit 0) /usr/local/bin/hda-verb /dev/snd/hwC0D0 0x15 SET_EAPD_BTLENABLE 2
5. Reboot and the sound should be working.