Saturday, November 6, 2010

Installing X and GNOME for CentOS

Today, I was setting up my next laboratory for my course of Network Foundations. There are seven computers with Ubuntu (2) and CentOS(5) as operating systems.

I found that CentOS-based systems did not deploy any graphical user interface and I googled how to install gnome packages and I found this link. It explains how to install the X Window System and the GNOME Desktop Environment. The command is as follows (as root):

# yum groupinstall "X Window System" "GNOME Desktop Environment"

Nice, ;-)

Sunday, September 5, 2010


Last week, I watched an appealing desktop environment for Gnome to resemble the Mac OS desktop. I was very curious about it and I did a non-deep search and found this project Gnome theme named Mac-OSX. I did install it and it presented me a better desktop than my previous one. However, the dock panel present in real Mac OSX was not there. I googled for "mac like dock in linux" and found some interesting links:
  • This link explains a little bit about the AWN project and describes how to customize this window manager
  • AWN has a wiki site
  • This link explains how to start the awn window manager
I will restart my gnome session.

  • As root, run the following command: "yum install awn-extras-applets"

Saturday, August 7, 2010

Configuring and Installing HP Photosmart C4780 in Fedora 13

Yesterday I bought a HP Photosmart C4780. I didn't have many options because this multifunction device was the only in the shelf so my decision was obvious. However, I don't have any regrets since HP is characterized for its support to the open source community and thus it provides drivers for Linux systems, including my FC 13.

The installation procedure was almost straightforward and can be summarized in two parts, printer and scanner configuration.

The steps associated with the printer configuration were those:
  1. Verify that you have installed CUPS in your Linux system
  2. Execute the following command as root:
    yum install hplip-common hplip-gui hplip-libs hplip hpijs
  3. Go to and download the latest version of hplip. At this time, it is hplib-3.10.6.tar.gz. Despise you have already installed the hplib software, the required driver is not still available in your system. So untar the following files, as follows:
    tar xfz hplip-3.10.6.tar.gz hplip-3.10.6/ppd/hpijs/hp-photosmart_c4700_series-hpijs.ppd.gz hplip-3.10.6/ppd/hpcups/hp-photosmart_c4700_series.ppd.gz
Now, as root, run the 'run-setup' command. This program was installed during the yum procedure. This program will guide you through three basic steps. The former questions can be ignored but the last page will ask you about the driver. Select anyone of the files obtained in the step 3. Now, the wizard will ask you for restarting the cups service, do it.

Now, point your browser at http://localhost:631, add a new printer and select the "HP Photosmart C4700 series" option. Then, continue the configuration procedure as usual.
Verify that everything is ok, printing the test page :-D

For enabling the scanning procedure, I did execute the following steps:
  1. yum install gnome-scan gnome-scan-libs
  2. yum install libsane-hpaio
I did try "Scanner Utility" and "Simple Scan" applications from my gnome menu but none of them did the trick. So, I was looking around for a command line starting with the 'scan' word and I found it, scanimage.
Like other command line tools is not intuitive at all but its help output is, in fact, very helpful. My command line to scan a sheet is as follows:
  • scanimage -d hpaio:/usb/Photosmart_C4700_series?serial=CN04HM20GK05HD > salida.png

The parameter -d hpaio:/usb/Photosmart_C4700_series?serial=CN04HM20GK05HD indicates the device that will be used for scanning. The standard output would be redirected towards a PNG file, salida.png. Now, use your regular image viewer to see the results.

Any comments please let me know.

Saturday, July 10, 2010

Featured sites of the week

Welcome to this blog entry. Today, I want share some sites that I found profoundly valuable. Those sites present deep and interesting stories about culture, politics, economy, society and of course technology. Probably you know others also worth to follow sites but now I mention my favourites and frequently visited sites.
  • TED, it stands for Technology, Entertainment, Design. However, TED now embraces a larger group of topics where remarkable people talk about relevant issues with deep impact in our life, today and the days to come. I can mention some singular speakers, Al Gore, Brian Greene, Bill Gates, Sergey Brin, Larry Page, Billy Graham, among others.
  • NPR(National Public Radio), "is a producer and distributor of noncommercial news, talk and entertainment programming". I love its podcasts because they are short in time but present significant point of views that enlarge our singular point of view since they brought new perspectives about such a large amount of different topics. Today, I found other valuable asset of NPR, it not only provides podcasts but also transcripts of them which are so valuable for foreign people not only learning English but also looking for keeping informed.
  • OpenCulture, it provides very interesting short videos about culture in general. Videos exhibited are featured videos, if you will, about music, science, movies, ideas & culture, and so on. However, OpenCulture not only focus on videos but also it regards with free courses on a variety of topics such as language, biology, computer science, economics, engineering, math, philosophy, and many more.
  • H-Online, yesterday I found this site. It regards with open source and security topics. I'm a great fan of Linux as consequence a big fan of other open source projects. I don't have so much to say about it but I will put on eye on it and see what worthy to follow it is.
Your comments/suggestions are welcome and of course I would glad to know about your featured site(s).

Happy weekend.