How to control the brightness of the display from command line?

You can set the brightness of the display by issuing this command within a shell echo 3 > /sys/class/backlight/acpi_video0/brightness where 3 is the brightness level. Its value is from 0

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How to restore the normal scroll bars in Ubuntu 11?

Simply create a file named /etc/X11/Xsession.d/80overlayscrollbars and put into it the following line: export LIBOVERLAY_SCROLLBAR=0 or simply execute the following command echo “export LIBOVERLAY_SCROLLBAR=0” > /etc/X11/Xsession.d/80overlayscrollbars You need to do

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Install Ice Cream Sandwich on a Google Nexus S

I have installed Ice Cream Sandwich (ICS) on a Google Nexus S. It works perfectly. The process is not complicated but requires some basic technical skills. What’s interesting about the process

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Converting a certificate from DER to PEM or PEM to DER

openssl x509 –in input.pem –inform PEM -out output.der –outform DER openssl x509 –in input.der –inform DER -out output.pem –outform PEM

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How to remove the passphrase on a private key

To remove a passphrase on a private key, simple execute this command. openssl rsa -in server.key -out server.unprotected.key Since it is a private key, make sure that it is well

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Creating a certificate for a server

Creating a server certificate involves only a few steps. To do so, execute the following commands. This post assumes that “OpenSSL initial configuration” and “Creating a ca’s self signed certificate”

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Creating a ca’s self signed certificate

In order to create your own certificates, you need a CA (certificate authority) certificate. This certificate will be used to sign every certificate you will create. To do so, execute

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Tomcat and MySQL benchmarks

Benkmarks made using a Tomcat and a MySQL database. These figures are provided to give you an idea of the performance you should expect. The tests were done in the

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OpenSSL initial configuration

This initial configuration procedure assumes that you are executing it on Linux Create a special user named ‘ca’. Its home directory will hold the data. It must protected carefully. For

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How to change the signature of a disk

To change the signature of a disk under Windows 7, follow these steps are: Run the command line utility diskpart as the administrator user Execute the command “list disk” to locate

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Installation of the AVR toolchain on Ubuntu to develop for the Arduino Platform

Install Eclipse using “Ubuntu Software Center” Install the AVR Eclipse Plugin using Help >> Install New Software. The source link is http://avr-eclipse.sourceforge.net/updatesite/ Install the gcc toolchain apt-get install avrdude binutils-avr

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SSH login without password

It is possible to securely connect to a SSH server without a password. To do so, you must perform the following steps. It assumes that both machine are running a

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How to create a SSH tunnel

You can connect to a remote host [remote-host] using another machine [proxy-host]. This can be accomplished if the [proxy-host] as an SSH server running. To do so, logon to the

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How to replace LibreOffice by OpenOffice in Ubuntu 11

If you prefer using OpenOffice than LibreOffice in Ubuntu 11, you can replace it using these few steps: Download OpenOffice from http://download.openoffice.org/other.html. Download either Linux Intel DEB or Linux x86-64 DEB depending

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Unix History

I can bet that you have no idea what the Unix timeline looks like. Curious? Download this PDF file from www.levenez.com.

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USB Flash Drives comparison

Manufacturer Model Capacity Read speed(MB/s) Write speed(MB/s) Patriot Xporter XT Rage 32 GB 27 25 Corsair Voyager GTR 32 GB 34 28 Lexar Echo MX 32 GB 30 17 Kingston

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Very slow connection to a SSH server

A problem with the DNS configuration on a server can cause the login to the ssh server very slow. I can be fixed by adding the following line UseDNS no

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Exchange large files for free

When it is time to transfer files, e-mail has its limitation. Most of the time, e-mail size is limited to 5 megabytes or so. The site FileConvoy lets you share

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Arduino Ethernet Shield example WebServer.pde no longer works after upgrading Ubuntu to version 11.10

This patch must be applied to w5100.h located into library/Ethernet/utility. — w5100.h.orig 2011-10-03 13:43:10.536833701 +0200 +++ w5100.h 2011-10-03 13:47:26.764844567 +0200 @@ -258,7 +258,10 @@ } \ static uint16_t read##name(SOCKET _s)

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VPN connection times out under Ubuntu 11.10

After upgrading to Ubuntu 11.10 (Oneiric Ocelot), some VPN connection using Shrew (2.1.7) times out. Nevertheless, Shrew 2.1.5 still works under Ubuntu 11.10. The challenge is to uninstall version 2.1.7

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