Installation

Since Ubuntu 10.10, GeoGebra is in the official repositories. Therefore, you can install it via your favorite command line:

if you are using Gnome,

sudo apt-get install geogebra geogebra-gnome

or for KDE,

sudo apt-get install geogebra-kde

If you are under an older version of Ubuntu, or not using Ubuntu, I invite you to search for an additional repository, or take a look at the official download page for Linux.

First Steps

As I said earlier, GeoGebra is very complete at multiple levels. What I will try to do now is give you a little introduction to all of these levels. The first one is the most obvious use of the program: to draw geometric figures as if you were using the traditional compass and ruler. It becomes possible to draw a square with mathematical rigor, based on a circle, parallel and perpendicular lines only.

The objects that you can use are easy to access; you can select the option that you want from well-organized groups. For example, creating a perpendicular line is in the same category as the parallel ones. On the other hand, you can choose between a line and a segment from the same button.

A second level is the possibility to graph functions. It can become very handy to be able to trace a curve from a formula, and make a point move along it. For that, you can simply enter an equation like “y=2x” in the bottom text field, and the line will appear.

It then becomes possible to add a point on that curve as a linked object: even if you change the formula, the point will follow and stay on the curve. And opposite, you can modify the point’s properties via a dialog window.

You will also find a simple spreadsheet system within the program, with some basic functionality that a program of that type can offer. You can use formula, sort, and add data together. There is even a probability computation option.

Finally, GeoGebra integrates a certain level of scripting and user interaction. You can add an object like a cursor on the sheet. Moving it will affect a variable that you can name and use in other formulas. I made a basic example of that, I linked the cursor to a line defined by the equation y=2x+b. Moving the cursor along will change the value of b and therefore define the y-intercept of the line.

You can of course do some more interesting things with such system, and it is even possible for the experts to use some JavaScript or HTML5 to interact with GeoGebra.

Conclusion

If you want to go further in learning about the advanced functions of GeoGebra, you can go and take a look at the wiki. However, I think that the program is so well designed that you can solve most of your problems by inspection all by yourself. It is quite rare to find a program that is so complete on different level of usage and yet remains simple and well organized. As an alternative, I can also propose you software like Kig, Dr Geo, Geonext, CaRMetal.

What do you think about GeoGebra? Do you use it? Do you prefer and alternative? Or do you have a script that you would like to share? Please, let us know in the comments.

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Skype-wrapper is a plugin that integrates Skype with Unity. It adds the Skype icon to the messaging menu and quicklist items to the launcher. It also uses the Unity notification style to notify you of incoming calls/messages.

Installation

Open a terminal and type:

sudo add-apt-repository ppa:skype-wrapper/ppa
sudo apt-get update
sudo apt-get install skype-wrapper

The above commands assume that you have already installed Skype in your system.

Running Skype-wrapper

Once you installed Skype and Skype-wrapper, you will find that there are two instances of Skype in your computer. You need to identify which is which and run only Skype-wrapper, and not Skype.

1. Open Nautilus File Manager and navigate to “usr/share/applications”. Scroll down the application list till you see two Skype icons.

2. To identify which one is which, right click on the Skype icon and select Properties. The one that shows the “skype-wrapper” in the Command field is the one that you want. Drag this icon to the Unity Launcher.

3. Click on the icon to launch Skype. A popup will appear to prompt you to grant access to the skype-wrapper app. Check “Remember this selection” and click “Yes”.

Once it is authorized, you should see the Skype entry in the messaging menu and any incoming notification will follow the Unity style.

Right clicking the Skype icon on the launcher also show the quicklist items. You can View Incoming Message and Add Contacts.

Skype-wrapper also comes with a Settings option that allows you to configure its behavior. From the dash, search for skype-wrapper and you should see the “Skype-Wrapper Settings” app. In the Settings, you can configure the events to show notification and whether the file transfer progress should appear in the launcher.

Removing Skype icon from the systray

After the unity integration, there is one thing left that you need to get rid of. If you can’t stand the green Skype icon that didn’t go well with the Unity theme, you can remove it by uninstalling the “sni-qt” package. Note that a few other application, such as Dropbox, depend on the “sni-qt” package to display icon in the systray, and removing this package will affect these apps as well. Here’s what you need to do:

sudo apt-get remove sni-qt

The next time you launch Skype-wrapper, the green Skype icon won’t be around anymore.

Uninstalling Skype-wrapper

To completely remove Skype-wrapper from your computer, first open up your Skype option and go to “Public API” (the last option in the left sidebar). Select “Skype4Py” and click Remove.

Next, uninstall skype-wrapper from your computer:

sudo apt-get autoremove skype-wrapper

That’s it.

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Geary is a simple and lightweight email client that supports email threading (some call it conversation mode). It is still in the early development stage, but it does show plenty of potential to become a great email client.

Being a simple and lightweight app, Geary has trimmed most, if not all, of the fat found in many other email clients. It is pretty simple in interface and features, and yes, it is also lacking some important functions like integrating with address book and connect to multiple email accounts.

Installation

Here’s the command to install Geary in ubuntu-based distro:

sudo add-apt-repository ppa:yorba/ppa
sudo apt-get update
sudo apt-get install geary

Running Geary

The first time you run Geary, it will prompt you to setup your email account. There are three options in the “Service” dropdown: Gmail, Yahoo and Other. If you have enabled IMAP in Gmail and Yahoo, all you need to do is to enter your username and password and it will do the rest. For the “Others” option, you will have to configure the IMAP settings manually.

Once your account is authenticated, you should see your mails appearing in the main window.

The interface is pretty minimal. There are three columns that show the folders, email list and actual email content respectively.

At the top is a row of toolbar that allows you to reply, forward, compose and archive your emails and that are about all you have for Geary.

The best thing about Geary is the threaded conversation that makes the interface more compact and each email message easier to follow. The thread count is displayed in the email list and the conversation is threaded, just like the way Gmail does.

There are also several other Gmail-like style, like the labels, starred, archive etc.

When it comes to composing email, it is pretty basic and lacking at the same time. You can compose in rich-text format, but you won’t be able to attach any file to the email. It doesn’t integrate with your contacts as well, so you have to manually type in the email address of the recipients. I wonder how many people actually remember all the email address of their friends.

Removal of email account

As of this post, there is no easy way for you to remove the email account you have setup in Geary. The only way I can come up with is to go to the “~/.local/share/geary/” folder and remove the folder with your email address. This will effectively remove the email account in Geary.

Conclusion

The advantage of Geary lies in its simplicity. Being a lightweight application with Gmail-like interface (labels, starred, threaded conversation) makes it easy and pleasant to use, but the lacking of several features such as contacts support and file attachment etc have severely crippled the app. Noting that this is still a product in its early development stage, hopefully these important and necessary features will be integrated into the app. By then, it could become the default Gmail desktop app, much like the way Sparrow does for Mac.

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Configuration

First of all, you will need the “ntp” package on your computer. On most distributions, it is installed by default, but you may want to check that you have it or its equivalent. To check, try the command

ntpq

And if it is not found, you know that you don’t have the appropriate package.

Now that this is done, the entire configuration is going to be made with the file “/etc/ntp.conf.” All you have to do for an instant result is to modify these lines which are the default ones:

 server 0.pool.ntp.org
 server 1.pool.ntp.org
 server 2.pool.ntp.org
 server 3.pool.ntp.org

Instead, there are two things you need to do:
Find the addresses of the time servers closest to you on pool.ntp.org and copy-paste them instead of the default ones. As an example, the addresses for the U.S. are

server 0.us.pool.ntp.org
server 1.us.pool.ntp.org
server 2.us.pool.ntp.org
server 3.us.pool.ntp.org

Add “iburst” at the end of each server lines. This option will send a “burst” of packets in case the initial connection with the server fails.

So, in the end, if you are in the U.S., your addresses should look like that:

server 0.us.pool.ntp.org iburst
server 1.us.pool.ntp.org iburst
server 2.us.pool.ntp.org iburst
server 3.us.pool.ntp.org iburst

Synchronization

Now that the servers are correctly setup, you can launch the synchronization process. You may want to first test that the connections are working and that the servers are up. For that, use the command

 ntpq -p

If you see something like this, then you’re fine. 

Then, the easiest way to synchronize is to add ntp as a daemon. Edit your “/etc/rc.conf” file (or the equivalent, depending on your distribution) to add “ntpd” after your Internet connection daemon. In this case, you will have to blacklist the hwclock daemon. So your rc.conf file should contain something like:

 DAEMONS=(...[Internet connection like wicd]...!hwclock ntpd...)

An alternative if you don’t want it as a daemon is to launch the command

 sudo ntpd -qg

And then update your system clock with

 sudo hwclock -w

Note that in some circumstances, your clock should already be broadly at the right time, but off by a few minutes. The synchronization may not work if your time differs by a couple of hours from the servers’ time.

Conclusion

With this, your clock should always indicate the right time. Overall, I find the configuration and the synchronization to be pretty straightforward. It’s still more complex than it is with Ubuntu, but it is the price that those who want more control must pay. Alternatively, systems like Chrony and OpenNTPD offer the same service, and work generally in the same way.

Do you use ntpd? Or do you prefer some other service? And which method do you use for your synchronization? Please let us know in the comments.

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Installation

To install sysstat on a RedHat based variant using yum:

yum -y install sysstat

To install on a Debian based variant using apt:

apt-get install sysstat

If you are using a Ubuntu-based distro, you should be able to find sysstat in the software manager.

After the installation, you will need to edit the configuration file to run the daemon.

In the terminal:

gksu gedit /etc/default/sysstat

and set the “sadc” variable to true by changing the line to ENABLED="true".

Save and close the file. Finally, start the daemon:

/etc/init.d/sysstat start

Common usage of Sysstat

The sysstat suite is obviously a collection of very extensive and detailed application. Here are some basic ways to use the tools in order to gain a feel for its troubleshooting guidance.

Check CPU usage

To check CPU usage stats for the current day (by default sar tracks the data every 10 minutes):

sar -u

To display real-time CPU usage for a given amount of time, you can specify the intervals in seconds followed by how many entries you want to report. For example: the following will report total CPU usage every 2 seconds for a total of 10 times:

sar -u 2 10

Most PCs have multiple cores nowadays. To view the activity of each specific core use the “-P ALL” flag. The following shows a real-time snapshot of the 4 cores in my PC (same intervals and output parameters apply, below is 1 second 1 time):

sar -P ALL 1 1

Want to see how much memory is currently being used? Use sar -r as follows to show real-time memory usage every 2 seconds for 10 times:

sar -r 2 10

Display device report

To display a device report showing transfers per second (tps) and data read and write stats, showing data in real-time every 2 seconds, for 10 reports, type:

iostat -d 2 10

Note:

• tps = transfers per second
• Blk_read/s = amount of data read in blocks per second
• Blk_wrtn/s = amount of data written in blocks per second
• Blk_read = total blocks read
• Blk_wrtn = total blocks written

For extended I/O stats:

iostat -x 2 5

Get information regarding running process

Use pidstat to report information regarding running process. The -d flag will list all processes on the machine:

pidstat -d

To see real-time results of running processes, you can use the following, where like the above examples, the first number is the second interval and the second number is how many times to report:

pidstat - d 2 5

Another useful command is to use pidstat with the -r flag to analyze memory usage with particular processes:

pidstat -r 2 5

Conclusion

Sysstat is a very powerful monitoring tool for Linux and it is particularly useful in a server environment where there is no GUI available. The above mentioned only touch the surface of what sysstat is capable. If you have used sysstat in your PC/server, feel free to share with us the various ways you use it to monitor your system performance.

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Sun JDK vs OpenJDK

In the past, Sun JDK was the default java package in Ubuntu. After Sun Microsystem was acquired by Oracle in 2010, Ubuntu (and various distros) switched the java package to the fully open-source OpenJDK as the SUN JDK no longer contain codes that are fully open-sourced.

OpenJDK is community-built and is (almost) 100% similar to the SUN JDK. You can easily install OpenJDK in Ubuntu via the Ubuntu Software Center, by clicking here or running the command:

sudo apt-get install openjdk-7-jre

Personally, other than some minor font rendering issue with OpenJDK, I have not experience any major problem with OpenJDK. That could also because I don’t use many java-based apps in the first place. However, if you have a specific java-based app that don’t run well in OpenJDK, you can switch to the SUN JDK instead. Here is how you do it:

The hard way

This method requires you to install SUN JDK 7 manually. It is a good way for you to learn the trick.

1. Download the SUN JDK 7 here to your home folder.

2. Extract the tar file.

3. Move the extracted file to the “/usr/lib/jvm/” folder:

sudo mv jdk1.7.0_04 /usr/lib/jvm/

4. Install SUN JDK 7 in your system:

sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk1.7.0_04/bin/javac 1
sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk1.7.0_04/bin/java 1

5. Set the environment variables:

sudo update-alternatives --config javac
sudo update-alternatives --config java

You will see an option like the screenshot below:

Enter the option that corresponds to the SUN JDK package. Press Enter.

That’s it.

To test your java:

java -version

You should see something like this:

The easy way

If you don’t want to manually install the SUN JDK, you can do it via a PPA. Since there is no official PPA for SUN JDK, you will have to grab a custom PPA that comes with the java package. Note that custom PPAs might add extra software sources to the repository, and cause your system to be bloated or even have conflicts with other apps. So bear in mind the risk involved.

There are several PPAs out there that come with SUN JDK, one that you can use is “webupd8team/java”

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java7-installer

This should install SUN JDK 7 in your system.

Run Java applet in Browsers (Firefox, Chrome etc)

Even after you have installed the java package, you will find that the java applet in your browser won’t run. If you are using the OpenJDK, here is another package that you need to install:

sudo apt-get install icedtea-7-plugin

For Oracle java, run the commands:

mkdir ~/.mozilla/plugins
ln -s /usr/lib/jvm/jdk1.7.0_04/jre/lib/i386/libnpjp2.so ~/.mozilla/plugins

If you are using a 64-bit system, remember to change the “i386″ to “amd64“.

Once install, restart your browser. The java applet should run now. To test if Java is working in your browser, go to http://java.com/en/download/testjava.jsp. If installed correctly, you should see a “Your java is working” message.

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1. sl

Thanks to Asdasd, I discovered “sl”. An incredibly useless but very necessary program that just shows a train in ASCII art going through your terminal. Maybe one of the most appealing commands of this top ten.

2. pi

Credit goes to cameronhorsburgh for bringing this one up. “pi” displays an approximation of PI, useful if you are making some calculation, I guess. The syntax is:

pi [number of digits to display]

3. dog

Coats was the one to bring this one up. “dog” is an alternative to “cat” (see the humor?), as it uses the same syntax to display a text stream into the console. You will probably have to install it as it is not a command offered by default, but when you do, I invite you to take a look at the manual page.

4. vdir

“vdir” is useless in that it is a redundancy. Its main function is to list the content of a directory, displaying the name of the files, the permissions, the dates of modification, the sizes, etc. However, all of this can be done via the good old command “ls” and its composite like

ls -l

5. clear

“clear” is also a redundancy. With this command, you will erase the lines from the terminal and “clear the screen.” But anyone adept with the console will save time by using the shortcut “Ctrl+l”, which does exactly the same thing.

6. ul

An interesting command, “ul” can be used to underline characters in the terminal. I still have not figured it out completely but I know that, for example, it will transform

echo $'hello w\b_o\b_r\b_l\b_d\b_ ' | ul

into “hello world“. As you can guess, it replaces the meta-character “\b_” with an actual underlining.

7. w

You can say whatever you want about “w”, but it is to my knowledge the shortest command you can find by default on your machine. And I think that it therefore deserves to be in our list just for that. Surprisingly, “w” allows you to see information about the current users, like their name, their login time, etc.

8. filters

A moore’s contribution: filters is a set of tools that transforms text to give it some phonetic accent. “man talkfilters” will give you the list of the possible accents. But as an example,

echo "make tech easier is cool" | fudd

will give “make tech easiew is coow ” which supposedly imitates Elmer Fudd’s accent (the guy who hunts Bugs Bunny in Looney Tunes). And one of my favorites, the filter “warez” will give you your input in H4x0r code. The previous example becomes “]\/[ak3 73k]-[ 3az13r YZ c0ol" with "warez" instead of "fudd" at the end of the command.

9. fortune mods

Last time, I presented to you the famous fortune command which gives you a (relatively) short and random geek sentence each time you call it. However, if you can add your own fortunes to the database, it is also possible to download extensions, or mods, which add fortunes from a specific source, like Star Wars, the Chuck Norris facts, different languages, Matrix, Futurama, Calvin and Hobbes, and more. Install the mod that you want and do

fortune [name of the mod]

As an example, I installed the Chuck Norris fact extension in English, so by doing

fortune chucknorris

I get "Chuck Norris grinds his coffee with his teeth and boils the water with his own rage."

10. snow

Finally, a little script to end the top ten. I could not stop myself from sharing the snow.sh script from myh3r3.com which creates little snowflakes falling into your terminal. Copy-paste the code into a text file, name it "snow.sh", make it executable, and launch it in a terminal to admire.

#!/bin/bash
 
LINES=$(tput lines)
COLUMNS=$(tput cols)
 
declare -A snowflakes
declare -A lastflakes
 
clear
 
function move_flake() {
i="$1"
 
if [ "${snowflakes[$i]}" = "" ] || [ "${snowflakes[$i]}" = "$LINES" ]; then
snowflakes[$i]=0
else
if [ "${lastflakes[$i]}" != "" ]; then
printf "\033[%s;%sH \033[1;1H " ${lastflakes[$i]} $i
fi
fi
 
printf "\033[%s;%sH*\033[1;1H" ${snowflakes[$i]} $i
 
lastflakes[$i]=${snowflakes[$i]}
snowflakes[$i]=$((${snowflakes[$i]}+1))
}
 
while :
do
i=$(($RANDOM % $COLUMNS))
 
move_flake $i
 
for x in "${!lastflakes[@]}"
do
move_flake "$x"
done
 
sleep 0.1
done

Conclusion

First, I want to thank you all for your comments on the previous article. I tried to put here a synthesized version of what you reported in order to share it with more people. Of course, this list is still not complete, and even if I personally doubt that it will ever be, I still invite you to continue to share.

So again, if you can think of more, or if you have an example in mind of when these commands become handy, please leave us a comment.

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• 10 annual license: $139.00
• 50 Annual License: $199.00
• 100 Annual license: $299.00
• 250 annual license: $399.00
• Unlimited: $499.00
• Unlimited Lifetime: $999.00

The Virtualmin download page list the steps to install Virtualmin on your server.

Note that Virtualmin has a setup script that makes installation easier, but it will only work with certain operating systems (Virtualmin calls them grade A):

• CentOS 5 and 6 on i386 or x86_64
• RHEL 5 and 6 on i386 and x86_64
• Scientific Linux 6 on i386 and x86_64
• Debian 6 on i386 or amd64
• Ubuntu 8.04 LTS and 10.04 LTS on i386 or amd64

You can use Virtualmin with other server OS’s, but the script will probably not work, which makes installing a bit more of a hassle. There is a way to “fake” the install script to thinking it’s installing on a grade A OS. For example, if you want to install Virtualmin on Ubuntu 11.10, a simple change will make the install.sh script think it’s being installed on versions 10.04 LTS. (no guarantees that this will work with every system)

nano /etc/issue

replace “Ubuntu 11.10 \n \l” with “Ubuntu 10.04.02 LTS”

Save the file (Ctrl + o) and exit (Ctrl + x)

Note: The Ubuntu LTS (long term support ) releases are considered grade A by VirtualMin, but as of this writing Ubuntu’s 12.04 LTS is not listed.

Install Virtualmin

Download the script:

wget http://software.virtualmin.com/gpl/scripts/install.sh

or

curl http://software.virtualmin.com/gpl/scripts/install.sh

Make the script executable:

chmod u+x install.sh

Run the install script:

/bin/sh install.sh

As long as you have a grade A system (or at least fake that you have one), the script will handle the entire install process. When it’s finished, all you need to do is open a browser and go to port 10000 on that server:

https://yourdomain.com:10000

What can you do with Virtualmin? Pretty much everything. There is a dashboard where you can see all the running processes and services. You can customize it to show you the data you want to see. An administrator can easily use Virtualmin’s interface to do almost every task imaginable: Modify DNS settings, configure email settings, schedule backups for all of your virtual servers, manage plugins and applications, manage services, and much more.

Screenshots

Try Virtualmin yourself by using the free online demo.

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Note: This article assumes that the VPN you are connecting to is using a PPTP protocol. If you need a L2TP connection, the instruction below won’t work.

1. In your Ubuntu desktop, go to “System Settings -> Network”

2. At the Network window, click the “+” button at the left bottom corner.

3. When prompted, select VPN for the interface dropdown. Click “Create”.

4. Select “PPTP” for the VPN connection type (in most cases, you should only have one option). Click “Create”.

5. Give this VPN connection a name and enter the connection detail.

For some VPN connection, you might need to select the appropriate authentication method. In this case, click the “Advanced” button and check/uncheck the authentication method required for your VPN. Most of the time, you will have to disable the MSCHAP authentication and enable the “Use Point-to-Point encryption (MPPE)” optioni and select 128-bit security, but this could vary with each VPN connection.

Finally, click Ok and then Save to close out the previous window.

6. Lastly, click Save. You should be able to connect to this VPN by clicking the wireless icon at the system tray.

Done.

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• How to Upgrade to Gimp 2.8 in Ubuntu

What’s new in Gimp 2.8

Single Window mode

All previous versions of Gimp come with separate windows for the toolbar, main window and various dock dialogs. Some love it as it allows them to micro-manage, but some hate it and yearn for a Photoshop-like interface. In Gimp 2.8, the default interface is still the separate window mode, but you can get it to show the Single Window mode by selecting the “Windows -> Single-Window Mode” option.

Multi-column dock windows

GIMP 2.8 allows dockable dialogs in a dock window to be placed in multiple columns. To create a new column in a dock window, drag and drop a dockable dialog on the vertical edges of the dock window. This is an appealing feature for multi-monitor users where one screen can have a big dock window with all the dialogs and the tools, while all images are on other displays

Layer Groups

Gimp users with a Photoshop background will love this. In Gimp 2.8, you can organize your layers into group. Layer groups are also fully scriptable, making it easier and faster for you to get things done.

On-Canvas Text Editing

This is one feature that I love most. In previous version of Gimp, the text-editing feature always open in a new window, making it very troublesome to handle. The on-canvas text editing in Gimp 2.8 allows you to make changes on the canvas itself.

Simple Math In Size Entries

While resizing an image, you can now use simple Maths as the input size. For example, rather than calculating half of 768px, you can now input “0.5*768″ into the width/height field. You can also input “30%” in the field without having to change the unit from “px” to “percent”.

For more changes, refer to the complete Gimp changelog.

Install Gimp 2.8 in Ubuntu 12.04

Ubuntu 12.04 is still running Gimp 2.6. For those of you who can’t wait for Ubuntu to include Gimp 2.8 in the repository, you can upgrade to Gimp 2.8 via the following method:

1. Uninstall Gimp from your system:

sudo apt-get autoremove gimp gimp-plugin-registry

2. Add the following PPA:

sudo add-apt-repository ppa:otto-kesselgulasch/gimp
sudo apt-get update

3. Install Gimp:

sudo apt-get install gimp

Configuring plug-ins and scripts for Gimp 2.8

Updated: The “gimp-plugin-registry” package has been updated to work with Gimp 2.8. The instruction below is no longer necessary.

The “gimp-plugin-registry” package in the repository is not compatible with Gimp 2.8, so if you are using plenty of plug-ins, you won’t be able to install them via the “gimp-plugin-registry” package. The only way is to manually install the plugins (until the plugin registry package is updated). Most of the scripts should continue to work though. I place the “arrow.scm” script in the “.gimp-2.8/scripts” folder and it works perfectly.

Here is how I install the “Save for Web” plugin:

1. Download the “gimp-save-for-web-0.29.3.tar.bz2” file to your home folder.

2. Extract it to the “.gimp-2.8/plug-ins” folder.

3. Open a terminal and type:

sudo apt-get install libgimp2.0-dev intltool
cd /home/your-username/.gimp.2.8/plug-ins/gimp-save-for-web-0.29.3
./configure
make
sudo make install

If everything goes smoothly, you should be able to use the “Save for Web” feature in Gimp 2.8 now.

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Installing from Scratch

First, you will need an Ubuntu Alternate CD. For this example, I took a classic 10.04 i386 ISO from here. In case you don’t know, an alternate CD is like the regular one but without the fancy interface for installing Ubuntu, and it lets you access more options. Among these is the ability to hit F4 at boot to select “Install an LTSP server” from the different modes.

The installation will then take as usual when an alternate CD is used:

• Select your language
• Select your country
• Select your keyboard layout (automatically or manually)
• The DHCP will configure itself
• Choose a host name

• Set the clock
• Select your partition system (full disc, partial, encrypted, etc.)

• The installation will begin. It can take a few minutes
• As usual, choose a user name and a password

• Decide if you want to encrypt your /home
• The image will be compressed

• And finally, the GRUB boot loader will be installed

And that’s it. You can now reboot and connect your first thin client.

Notice that even if the automatic installer is great, some manual configuration may be needed in some cases.

I advise you to take a look at “/etc/ltsp/dhcpd.conf” and “/opt/ltsp/i386/lts.conf” for the advanced settings. The LTSP Wiki is very informative.

If you want to transform your computer into a thin client server without having to re-install everything, LTSP can also do that. Simply install the required packages:

sudo apt-get install ltsp-server-standalone openssh-server

And then launch the automatic configuration process via

sudo ltsp-build-client

It will take some time to retrieve and install everything.

It did not work out for me the first time but it was probably due to the bad Internet connection, so don’t hesitate to retry in case of failure. However, bear in mind that some manual configuration will generally be needed here. You can finally launch your server with

sudo /etc/init.d/dhcp3-server start

Conclusion

As I said earlier, LTSP can be installed on a plethora of other distributions, so you can pick your own if you want. Ubuntu can be considered as the standard for a tutorial but each distribution’s wiki is very precise and a lot more detailed. As a last piece of advice, you should check that your thin clients can be booted from the network because it is really a pain to do it manually if you have more than ten of them.

Would you pick another distribution to install LTSP on? Or would you choose something completely different from LTSP in the first place? Let us know your opinion in the comments.

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1. Decide whether to install from scratch or upgrade your existing version

In my past experience, upgrading an existing version of Ubuntu to the latest version always left a bad taste in the mouth. Downloads are slow, upgrade took forever and the completed product always break things here and there. This is worst if you are two or more versions behind as the transition from GTK 2.x (11.04 and below) to GTK 3.x (12.04) would undoubtedly break some of your applications and settings. However, I have read news that the upgrading process in Ubuntu Precise is much smoother and less things are breaking, so it might worth a try.

My advise is: if you are using a much older version of Ubuntu (11.04 and below), it is good to reformat your PC and install from scratch. This will rid your system of any old and useless files, applications and settings. On the other hand, if you are inexperienced with PC formatting, don’t wish to spend the extra time and effort to install from scratch and don’t mind things breaking (the breaking could be minimal if you are upgrading from 11.10), upgrading using the Upgrade Manager is your best bet.

2. Backup, backup and backup

No matter what, you should always backup your system. In case the upgrade fails and you have to re-install from scratch, you still can recover your files from the backup.

There are several things that you will need to backup:

Files and documents

Needless to say, you should always backup your important files and documents. One good way is to back them up to the cloud, using either Dropbox, Ubuntu One or Box. When combined, the 3 cloud storage services give you a whopping 57GB of storage space to use, which should be sufficient for most users. Alternatively, you can also use the built in backup manager – Deja Dup to backup your system. That will require you to use an external hard drive or partition.

PPAs

Most of us don’t just use the default applications in Ubuntu. Most of the time, we will install new applications using third-party PPAs. To save you the trouble from sourcing these PPA again after re-installing, you can backup your list of PPAs and restore them after the re-install.

There are two main places where your PPAs are kept. If you are using the add-apt-repository command or the Software Sources to add your repository, they are kept at the “/etc/apt/sources.list.d” folder. To backup this folder, you can use the command:

tar -cvzf myppas.tar.gz /etc/apt/sources.list.d/

This will create a tar file in your home folder. You can then move this tar file to your backup drive or Dropbox.

To restore, place the tar file in the Home folder and use the command:

sudo tar -xvzf myppas.tar.gz
sudo apt-get update

If you have added your PPAs manually, they are most likely to reside in the “/etc/apt/sources.list” file. To backup this file, use the following command:

cp /etc/apt/sources.list /your-backup-folder/

Replace the “your-backup-folder” with the actual filepath to your backup folder.

To restore,

cat /your-backup-folder/sources.list >> /etc/apt/sources.list
sudo apt-get update

That’s it.

Note: You will most probably have duplicate or obsolete PPA in the list after the restoration. You might want to use “sudo nano /etc/apt/sources.list” to remove the unwanted PPAs (follow by “Ctrl + o” to save and “Ctrl + x” to exit) before you run the “sudo apt-get update” command.

Backup config files

The config files are one thing that many people overlooked while backing up their systems. Failing to backup the config files won’t break your system, but you will have to manually configure the settings for each app again.

In Gnome, the config files are usually stored in the “/.local/share” and “/.config” folders, but some apps could have their own config folders like “/.gnome2″, “/.VirtualBox”,”/.Thunderbird”,”/.wine” etc.

One good way to backup your config files is to setup your UbuntuOne account and sync these config folders. On your next install, UbuntuOne will automatically restore your config files to their rightful locations.

3. Test out with a Live CD first

This isn’t necessary all the time, but if you have some old applications that are critical to your business and you are not sure if they are supported in Precise, you can download the ISO file and test it with a Live CD or in Virtualbox. You can proceed to install after you have verified that it can fulfill your needs. In addition, for new user who are planning to switch to Ubuntu, testing with the LiveCD is the best way to find out if you really like the distro and whether you should switch from your existing OS.

Conclusion

It never hurt to be careful. While you are eager to jump onto the bandwagon and upgrade to the latest version, doing a little bit of housekeeping and backing up could save you tons of trouble later on.

What other precautions do you take before you upgrade your system?

Image credit: by BotheredByBees

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Installation

First of all, download the distribution’s image from the official website. The ISO is around 200 megabytes, so it should go fairly quickly. The image can then be used in multiple ways: you can perform a network boot, install the OS on the hard drive, use it as in a live session, or run network diagnostics or memory tests. I simply ran a live session as a test, but the other options are also straightforward.

First Steps

The desktop looks very similar to that of Windows. I guess the purpose is to avoid confusion for the majority of users.

But since 2XOS is a thin client system, we don’t really care about what the desktop looks like. It comes with all the necessary tools to configure and manage the physical computer, but the efforts are mainly focused on remote connections. In fact, the only side programs on the computer are Opera, Skype, and PDF Reader.

However, I really liked the system configuration tool, which I found very complete. It has what you expect from a configuration program in terms of resolution and other settings. In addition to that, it has been enhanced to manage the connections to the network efficiently, making easy join farms or getting information about the current one.

And my favorite feature concerns the backup settings: it is easy to save the settings of the current computer in order to import them to another one later. This feature can save you a lot of time, especially when you want to install a thin client system on a dozen computers in a row.

Finally, the icons on the desktop represent the most-used types of remote connections for a thin client, like Citrix and VMWare, and a nice shortcut: all you have to do is enter the address, the username, and the password, and you are done. The protocol you use doesn’t matter: the procedure is the same.

Conclusion

As I said earlier, 2X ThinClientOS is one among many. ThinStation is also quite popular and relatively similar, but I have to admit that I found 2XOS very simple to use. There are some features that you can generally expect with thin client systems, like the network boot, the Citrix protocol, or the boot-on-lan capacity. Maybe next week we will see how to install a special version of Ubuntu with a built-in thin client system.

If you know any other thin client systems, or have any experience to share about the subject, you can let us know in the comments right now.

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1. CentOS

CentOS is a community built distro based on the source code of RedHat Enterprise Linux (REHL). It is also the most popular distro for web server as of now. The benefit of using CentOS is that it is stable and seldom crashes. If you have some packages that only work with REHL, chances are you can get them to work in CentOS as well. Being the most popular distro, it also has the benefit of great support, either from their community forum, or anywhere on the Web.

Unlike most distro that has a 1 -2 years release cycle, CentOS took a (very) long time to release a new version (CentOS 5 was released in 2007, and it was only till Dec 2011 that CentOS 6 was released). The benefit of this is that once you get your server up and running, it will be in good shape for a long time without having to regularly upgrade to a newer version. In addition, it has a very long term support for all its release (CentOS-4 has 7 years of enterprise lifetime), so you know your server is in good hands for long term to come.

As for the cons, you might have difficulties running newer packages and making use of the latest technologies. If you are looking at cutting edge technology, CentOS is not for you.

2. Debian

If you are from a Debian background, then a Debian server would make a great alternative to CentOS. In terms of administration, both are similar, except that Debian uses “apt-get” and “.deb” while CentOS uses “yum” and “rpm”.

Debian has a long release cycle as well, though not as long as CentOS. Being a community distro, new versions of Debian are released only when the community regards them as ready for public. The benefit of this is that each stable release is indeed, stable. Debian doesn’t come with a server or desktop edition. There is only one image for you to download and install. The default will work as the server edition. Install a desktop manager and it becomes the desktop edition.

3. Ubuntu

The most popular Linux distro for the desktop has recently become a favorite for many web administrators, mainly because they are very familiar with it. Yes, if you are familiar with Ubuntu, you might want to go with Ubuntu server because everything from adding package sources, installing packages to finding support is at your fingertips.

Ubuntu releases a new version every six months and its Long Term Support release (for server) is every 5 years. This gives you a good choice of using either the LTS for stability or the latest release for cutting edge technology.

4. OpenSUSE

Even though OpenSUSE (not SUSE Linux Enterprise Server) is relatively unknown in the server arena and few people will recommend it as the first choice for web server, there has been a good demand for it and many web hosts have already offered OpenSUSE in their library of images.

OpenSUSE is the free and community version of SUSE, which provides enterprise Linux, much like what RedHat is doing with its RHEL. OpenSUSE uses the RPM package, but that doesn’t mean it is fully compatible with RedHat or Fedora’s package, do this is something that you should take note of.

Personally, I have not used OpenSUSE as a server before, so I do not know how it performs. However, I did seen articles claiming that OpenSUSE (as a server) is faster and more stable than CentOS. I am not sure of its validity, but if you are experienced and comfortable in using OpenSUSE, you can definitely use it for you web server.

Others

Other distros not mentioned above include Fedora, ArchLinux and Gentoo and the premium ones include RedHat Enterprise Linux and SUSE Enterprise Linux. Personally I would not recommend Fedora, ArchLinux and Gentoo. Fedora is too cutting edge for me, while Arch Linux and Gentoo require plenty of configuration, making them hard to maintain. If you can afford the cash and need professional support, RHEL and SEL are few of the best out there.

Conclusion

There is no absolute best or worst distro for server usage. Most of them are similar and all have their own pros and cons. If you are administering your own server, the most important factor is the ease of use and that depends on your usage experience and familiarity with the distro. The rule of thumb is, choose the distro that you are most comfortable with and have the most experience in. It will give you less trouble while administering it.

Which is your favorite Linux distro for web server?

Image credit: 3d rendering of a server room with black servers by BigStockPhoto

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Linux basics

During the installation of Linux, it will prompt you to create an user account and set your own password. Once the installation is completed and the system rebooted, you will be prompted to login to the user account that you have previously created. Once you are in this user environment, you are your own administrator and you can run applications and customize the desktop to your own liking. This is pretty much the same as in Windows and Mac. You also have your own personal Home folder where you can add/remove any folder to and from it. That is pretty much everything you can do. Outside of your Home folder (i.e, the root folder), you will find that most (if not, all) of the file systems are not accessible to you.

While you can access and read the files in those folders, you won’t be able to make changes to them. The reason is because you don’t have sufficient permission.

User Permission

The user permission feature is one security feature that protects Linux users. With your administrator account, you are given permission to manage everything within your Home folder (and the external partition or hard drive that you have mounted). Outside of that, you will need root permission to make changes to the system file, including installing and uninstalling applications. The separation of the administrator account and the root account makes sure that you don’t mess up your system unnecessary and makes it harder for hacker/virus/malware to get into your root system.

Note: Unlike Windows, being the administrator of your own user account doesn’t mean you have root access to the system. You can’t just install/uninstall applications just by double-clicking on the the installer. In Linux, you will have to enter your password to elevate your user account before you can install/uninstall an app. This also means that things don’t get installed unless you give explicit permission to.

The existence of “sudo” and “su” is to allow you to gain root access so you can become the true administrator of your own system.

SU

“su” stands for “superuser” and allows you to login as root and do whatever you want with the system. It can be run with the command:

su

and it requires you to enter the password of the root account. In some distro, particularly Ubuntu, the root password is not set during installation. This makes it practically impossible to login as root (using “su”) since it cannot be authenticated.

If you really need to use the “su” command to get root access, you can change the root password by using the command:

sudo passwd root

By default, “su” logs you in as root in your own user environment. To change the user environment to root, use the command:

su -

Other usage of “su” include:

• Switching to another user who is not the superuser

su <username>

• Switching to another user and use that user environment

su - <username>

As can be seen, using the “su” command gives you great power to administer and modify your system, and if unchecked (or if you are inexperienced), it could be destructive to your system.

Note: As much as possible, do not to use “su” to administer your system.

SUDO

“sudo” stands for “superuser do” and it allows you to elevate your current user account to have root privilege temporarily. This is different from “su”. With “sudo”, you are still using your user account, but with root privilege, whereas in “su”, you are logged in to the root account. In addition, the root privilege in “sudo” is only valid for a short period of time. Once it expires, you have to enter your password again to regain root privilege.

With “sudo”, you can do pretty much the same stuff as “su”. To use it, you just have to add “sudo” in front of all root commands, for example:

sudo apt-get update
sudo apt-get upgrade

• In some instances, if you really need to login as root, instead of using “su”, it is better to use:

sudo -i

to start a root shell. This allows you to login as root with your own user password.

• You can also login as another user

sudo -i -u <username>

Conclusion

This is a basic introductory article to “sudo” and “su”. If you are a newbie, it is advisable to keep your hands off “su” and use “sudo” if required. For basic users, using “sudo” for most root commands suffice. For over 6 years of using Linux, I have not come across an instance where I need to use “su” or “sudo -i”.

For administering server, some will argue that you need to be root all the time to carry out maintenance and perform any other task. This may be true, but in my personal experience, if you install “sudo”, create a new user and add this user to the sudo group, you can do pretty much everything with the limited user account and sudo command. In fact, I would think this is a more secure way of administering your server. Tell me if I am wrong.

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Installation

There are no official packages (yet) for Ubuntu, so if you want to install Qute, the fastest way for any distribution is the official website. Download the file, decompress it, and launch the executable “Qute”. A first good point about it: Qute is pretty small and can be easily installed or put on a USB drive. However, do take note that some advanced features may require an extra package called PANDOC.

Features

What I like about Qute is that it has everything that you expect a light text editor to have, plus some advanced features and the eye candy that I promised you earlier.

It uses the standard UTF-8 format for encoding plain text files, and there is a full screen mode, as well as a split screen view. So far, everything is as expected. The shortcuts are also the same as in the common word editors: “Ctrl+s” to save, or F11 to go to full screen view. Notice, however, that the undo and the redo features are still not stable and that the results may vary.

In terms of visual interface, Qute comes with a lot of customization, like different backgrounds and fonts. You can choose to work on a wooden or on a dark gray background.

The menu is very smooth and fluid. You can open it via the escape key, or by clicking on the top left corner. Except for this, there are no apparent buttons or extra fields. Qute is very Spartan in terms of menus, but it’s a delight for the eyes.

Qute comes with some advanced and experimental features. One of my favorites is the fact that you can switch between the editing and the visual mode independently from paragraph to paragraph. This means that you don’t need to render or publish the whole file to see what it will look like in the end. To edit a paragraph, simply click on it. You then have to double-click again to switch back to the visual mode.

Qute also supports Tex, which means that you can write and edit Maths formulas pretty easily. It is then possible to export the file to a plethora of formats, amazingly for such a little editor: plain text, clipboard, HTML, PDF, LaTex, etc.

Finally, the program presents an experimental function: the ability to define your own language via OMeta syntax. I am not very familiar with this feature, and it is still in development, but so far, the demo shows how a user will be able to construct his or her own custom markup language.

Conclusion

As a final word, I will say that Qute is pretty convincing for an early version. It still lacks a little of stability and some functions like undo, but I am pretty seduced by its appearance already. On a side note, the project is under AGPL license; the source is on github, and developers and contributors are welcome if they want to help and bring the last features to life.

What do you think of Qute? Are you seduced or repelled by its characteristics? Do you know another similar text editor? Please let us know in the comments.

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The Advantages of using Symlink

The main advantage of symlink is that it is easy to create and doesn’t affect the system when deleted. Creating a symlink on your local folder pointing to the backup folder in the Network Drive makes it easier for you to access your files. Similarly, Dropbox users who wanted to sync multiple folders outside of the Dropbox folder can make use of symlink to get files synced easily.

In web hosting environment (particularly LAMP server), symlinks are heavily used to bring other parts of the filesystem to the Server Root. This allows the web administrator to have more flexibility in organizing and serving files to the Web.

On the other hand, when the targeted folder is moved or deleted, the symlink will fail to work. If you have created a lot of symlink and you love to move your folders around, you will have a lot of dead symlinks lying around. While they don’t take up plenty of space, they can become unsightly and mess up your filesystem.

Also, creating a symlink does not change the underlying user-permission of the files. If you create a symlink on your Home folder, pointing to a folder in the root directory, the file user-permission will not change. You will be able to access the files inside the folder, but you won’t be able to place files or edit the files in the symlink folder.

How to Create Symlink

The command line way

To create a symlink with the command line, you just have to use the command ln with the -s flag. The syntax is as follow:

ln -s TARGET_FOLDER SYMLINK_FOLDER

For example, if you want to create a symlink on your Dropbox folder to sync all the beautiful wallpapers you have collected over the years, here is how you can do it via the command line:

ln -s /home/username/wallpaper /home/username/Dropbox/wallpaper

The above command will create a symlink folder named “Wallpaper” in the Dropbox folder, pointing to the “Wallpaper” folder in the Home directory. Any wallpaper you place in the Wallpaper folder will automatically sync to Dropbox.

Note: For illustration purpose, I am using absolute path in the above example. You can use relative path as well.

The file manager way

I don’t have the chance to use all file managers to test this function, but in Nautilus, you can easily create a symlink by righ-clicking a file/folder and select “Make Link”.

This will create a symlink file/folder in the same directory as the targeted file/folder. It should be easily identifiable with a symlink icon.

You can then rename the symlink and move it to another location. The relocation of the symlink won’t affect the result, but the relocation of the target file/folder will.

Managing the symlink

If you have no more use for the symlink, you can simply delete it and it won’t affect any file/folder in your system.

To change the target folder it is pointing to, there is currently no way to do it. You will have to delete the symlink and create another symlink pointing to another folder.

Is this article useful to you? Let us know in the comments.

Image credit: Link by Big Stock Photo.

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There are other GUI apps built to easily edit cron, such as Gnome-Schedule. However, if you don’t want to install any new apps Corntab is a great web based solution, especially if you are setting up a cron job on a computer that doesn’t have Gnome-Schedule, or isn’t compatible with it.

The uses for cron are pretty obvious, anything from scheduling backups to running custom scripts at specific times, to opening programs on a schedule, cron is the way to get it done.

Let’s start with scheduling a task that simply creates a timestamp every minute to a log file, first using the shell/command line. Then we’ll run through the same steps using Corntab, so you can see how easy it is to use. Creating a timestamp or any output to a log file is a great way to test that your settings in cron are working, and of course to monitor your schedule going forward.

Open a terminal. Before we start, it is best to know where to go for information. The manual for crontab can be found by typing:

man crontab

Sure, you can Google and find other tutorials and probably the manual pages online, but it’s always good to know your way around the command line!

The syntax for cron is as follow:

crontab [ -u user ] file
crontab [ -u user ] [ -i ] { -e | -l | -r } [-s]

• -l option causes the current crontab to be displayed on standard output.
• -r option causes the current crontab to be removed.
• -e option is used to edit the current crontab using an editor specified by the VISUAL or EDITOR environment variables.
• -u option specifies the name of the user whose crontab is to be tweaked. If this option is not given, crontab will use the current user who is executing the command.
• -s option appends the current SELinux security context string as an MLS_LEVEL setting to the crontab file before editing / replacement occurs (see the documentation of MLS_LEVEL in crontab. This is not used in all variations of Linux/cron).

Note that some programs need to be executed with root privileges.  When this is the case, you will need to change to the root user with the su command, or the sudo command which should work in most Linux variations (Debian, Ubuntu, Fedora).

To edit your crontab type:

crontab -e

or

sudo crontab -e

Some ground rules for cron

• A field may be an asterisk (*), which always stands for “first-last”.
• m -minute (0-59)
• h -hour (0-23)
• dom -day of the month (1-31)
• mon -month of the year (1-12)
• dow -day of the week (0-6 with 0=Sunday)
• command -application, script, etc

Advanced Short codes:

string         meaning
——         ——-
@reboot        Run once, at startup.
@yearly        Run once a year, “0 0 1 1 *”.
@annually      (same as @yearly)
@monthly       Run once a month, “0 0 1 * *”.
@weekly        Run once a week, “0 0 * * 0″.
@daily         Run once a day, “0 0 * * *”.
@midnight      (same as @daily)
@hourly        Run once an hour, “0 * * * *”

Comma-separated values can be used to run more than one instance of a particular command within a time period.

Dash-separated values can be used to run a command continuously.

Let’s set up our cronjob.

If you are first entering crontab you will probably be given a choice of editor to use. Feel free to choose any, but I normally stick with nano since it is simple, clean, and gets the job done.

To accomplish our original task, simply type:

* * * * * echo "The current minute is: $(date)" >> /tmp/minute.log

“Control-x” will prompt to save, then enter will confirm. You should see that cron was successfully updated. The job will print the current date/time every minute to a file called minute.log in the /tmp directory.

Here’s the automatic output for 6 minutes:

Let’s get fancy, how about printing the date every 2 minutes…

*/2 * * * * echo “The current minute is: $(date)” >> /tmp/minute.log

Using */n where n is a positive integer will say every n minute, or every n hours.

How about printing the date at 5:30am every Monday and Friday:

30 5 * * 1,5 echo "The current minute is: $(date)" >> /tmp/minute.log

Feel free to play around with scheduling simple “echo” to logfiles. Then move up to scripts and applications.

Playing with Corntab

Now let’s try out CornTab, the web based cron editor that will take care of the syntax while we just click the options.

Here’s a step by step to create a crontab that will print the current date/time every two minutes, only in January, February, March, and April, on Thursday’s and Friday’s.

First, click “every n minutes” and move the slider to 2 minutes.

Next, click to expand month, click to select “each selected month” and select Jan, Feb, Mar, Apr.

Next, click to expand Day of Week, select “each selected day of the week” and select Thu and Fri.

Finally, click to expand Command and type in the code/script. Then you can copy the full cron code from Corntab and paste it into your crontab by using the steps at the beginning of this article.

References and more information about Cron:

http://www.pantz.org/software/cron/croninfo.html
http://www.computerhope.com/unix/ucrontab.htm
https://help.ubuntu.com/community/CronHowto

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1. Clementine

This one is my favorite (not for the reason that I like to eat Clementine) and this is why it is first in the list. Inspired by Amarok, it is a good looking and yet a feature-rich music player. Available for Windows, Linux and Mac, it seamlessly integrates with Ubuntu. Its main features include good iPod (and other portable music device) support, dynamic playlists, lyrics and artist information, album art discovery. It has a strong support for Internet Radio including big names like Last.fm, Spotify, Grooveshark, Jamendo, Magnatune among numerous others.

Clementine

2. Nightingale

Remember Songbird, the loved music player which ditched Linux 2 years back? Well, the legacy of Songbird has been continued by a fork of it: Nightingale. It carries forward the awesomeness of Songbird. Features include great support for synchronization, song and artist info, easy playlists and definitely good looks. Shoutcast Radio and Last.fm comes integrated with it. Last.fm album art can be used to fetch album arts. The list of extension and add-ons is growing with continuous community support.

Nightingale

3. Audacious

For all those Winamp MP3 player lovers, here is Winamp for Linux – Audacious. A light weight music players which has uncanny similarities to the famed Winamp audio player (reason being that it is descendant of legacy Linux player XMMS which itself was modeled after Winamp). Unlike other players like Clementine or Banshee which focus more on managing the music library, Audacious focus more on music. Motto is simple, drag and drop the files to create a playlist, sit back and enjoy the music. No fancy stuff, Last.fm is the only luxury it has got. Oh yes! it has great customization options as it supports Winamp skins.

Audacious

4. DeaDBeef

DeaDBeef is a simple, light on CPU yet feature rich audio player for Linux. Unlike its name, it is definitely not dead but very much alive. It plays (almost) all major and minor type of music formats with album art display capability. Last.fm is supported along with several other plugins at disposal. Recently it has arrived on Android so people using both Linux and Android can enjoy the homogeneity on different platform.

DeaDBeef

5. Quod Libet

Good things come in small package. Quod Libet is one such small package. It tries to answer “Boy, I wish I could grep my music“. Yes, it has a really strong search features. Written in Python and based on GTK+, it provide you with all the basic features of an audio player apart from the fact that it can handle a large library. Features also include Internet radio and podcast. To an extent it resembles Rythmbox but only less complex.

Quod Libet

All these music players can be downloaded form their respective official websites, links are provided in headings. I would like to know your views on this list and your favorite music player. What do you say?

Image credit: Abstract music background by BigStockPhoto and Wikimedia

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• How to Play MP3s From The Linux Command Line
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1. Download newrez from gtk-apps.

2. Inside the zipped file, there should have two files – newresz and newresz-v. Extract the two files and place newresz in the “Home -> .gnome2 -> nautilus-scripts” folder. If the nautilus-scripts does not exist, create it.

3. Next, kill your nautilus by typing “killall nautilus” in the terminal.

4. At your desktop, right-click your mouse and navigate to “Scripts -> newresz”. You should see the following:

5. Enter the resolution size that you want to set, say 1280, or 1920 and click OK. If everything go well, your screen should automatically resized to the new width.

Problems you might face

1. The script does not work

1. Check to see if you are using Gnome.
2. I have tested it with an integrated intel graphics and it works fine. However, since it requires XRandr and several AMD and Nvidia grpahics cards do not play well with XRandr, you might experience problem with the script.

2. There is no ways to restore back to the original settings

To restore, you just have to run the script again and set it to the original resolution.

3. The resized screen shows a black border box and the mouse can’t move into the box

This happens when you are on Gnome 3.x and it is a known-bug that is yet to solve (as of this post). Try the alternative method listed below.

Alternative to newresz

Remember there are two files in the zipped folder? The other file, newrez-v is an alternative to newrez and should work in all systems. The trick here is to create a vnc server at a higher resolution and then starts a vncviewer in scaled mode.

1. Open a terminal and type:

sudo apt-get install vnc4server gdm

2. Next, open the newrez-v file with a text editor. Scroll down to the end of the file (at around line 81), change the value behind the depth to ’24′ and the geometry to the screen size that you want to set (for example: 1920 x 1080)

$server :99 -name marc41:newrez -depth 24 -geometry 1920x1080 >/dev/null 2>&1

Save and close the file.

3. Back to the terminal, run the newrez-v file (the one time need to be run from the command line. Subsequent launch can be done from Nautilus)

path/to/newrez-v

Remember to change the path to the exact location of the file. This will configure the vnc settings. Once it is done, it will run the default VNC viewer with the screen size you specified. If you have specified a larger screen size, everything will be shrink down and look smaller than the default.

Image credit: several monitors with magnetic resonance images by Big Stock Photo

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