how-to customize the login screen of Fedora 16

I must admit being away from GNU/Linux desktops’ evolution dealing everyday with CentOS and Ubunutu 10.4 via CLI. Distributions that, anyway, are far away from the frantic evolutions in terms of desktop environment UX provided by the most up-2-date trends.

But I’m preparing a virtual machine for a bioinformaticians’ post PhD course and we choose a modern distro for this. Given my skills and experience the choice went over Fedora.

So I’m playing a little around to see how the Gnome Shell behaves and decided, since I have some spare time, to customize it a little. I could not ever imagined in my wildest dreams that modifing GDM login screen would be such a PITA.

Luckily enough a 2010′s post from Alvin T. Enguillo is still the easiest method (and with this I’ve said it all if you read the article) to achieve this goal.

So, do you like the result?

the evolution of Firefox’s DMG icon

Over the last five years of Mac OS X usage I’ve been collecting some screenshots over my Ipernity‘s space.

The idea behind this was to see changes over times in the look & feel of apps I use the most and the fashions over the software of this platform.

How the Mozilla’s Firefox DMG icon has changed is a nice example of this.

Early 2009:

Mid 2009 – Early 2011

Late 2011

Don’t you think ?

Drupal Day 2011 – Rome

via roma2011.drupalday.it

December 3rd in Rome there will be the 2011′s DrupalDay. Are you interested ???

how-to fix the XS version of Scalar::Util error in CentOS / RHEL / Fedora

It’s being some month now that at work we have encountered a nasty problem with Perl’s module Compress::Zib usage in a tool developed by a colleague. At the moment to start the graphical rendering of a web page the system gave error to our users.

Searching in Apache2′s log I’ve encoutered many error of this kind:
dualvar is only available with the XS version of Scalar::Util at /var/www/html/$MY-APP-PATH/perl/Compress/Zlib.pm line 8

This is because the Scalar-List-Utils module precompiled in RHEL/Fedora/CentOS and similar does NOT have the support of XS weaken function.

You will see a lot of bugs issued on this topic in this part of Linux distro’s.

My solution was to install perl-Task-Weaken

In fact as we can read in the package’s description:

rpm -qi perl-Task-Weaken
...
URL         : http://search.cpan.org/dist/Task-Weaken/
Summary     : Ensure that a platform has weaken support
Description :
One recurring problem in modules that use Scalar::Util's weaken function is
that it is not present in the pure-perl variant.

This restores the functionality testing to a dependency you do once in
your Makefile.PL, rather than something you have to write extra tests
for each time you write a module.

Happy coding!

How-to install BioPerl on Mac OS X 10.7 “Lion”

As my Twitter‘s followers have read in the last two weeks I had the chance to play with an early 2008′s MacPro lend to me by a friend/colleague to play with.

Since Lion has escaped nearly at the same time we took the occasion to fresh install it and reconfigure everything again for it’s usual bio-informatics usage.

Bio-Perl was one of the first request I had and since it was not so trivial gathering infos here’s coming this post. Official website’s project says:

Welcome to BioPerl, a community effort to produce Perl code which is useful in biology.

The official, ‘suggested’, way to install this set of tools on the OS X platform is to use the tools provided by Fink.

The Fink project wants to bring the full world of Unix Open Source software to Darwin and Mac OS X. We modify Unix software so that it compiles and runs on Mac OS X (“port” it) and make it available for download as a coherent distribution. Fink uses Debian tools like dpkg and apt-get to provide powerful binary package management. You can choose whether you want to download precompiled binary packages or build everything from source.

Unfortunately in recent years the Fink project seems to have lost some of it’s vitalità and, while the project’s still alive and working hard for 64bit’s Lion compatibility, many contributors are abbandoning the platform for various reasons. Obviously the one maintaining BioPerl is one of those.

An interessing (and appealing, at least for me) way would have been trying the use of an Homebrew‘s formula. Homebrew is a project in many ways and goals similar to Fink,but more agile and really on the growing phase. But, given the strong and extended interaction between BioPerl’s packages and Perl system’s importance I preferred not to mix things up and chose a 3rd way.

Sources, command-line and Perl compiler, along with CPAN were my allies.

Since the BioPerl packagas will have to be available to any user of that machine I did a global installation using administrative’s privileges on the following command in Terminal.app:

perl -MCPAN -e shell

This took me to:


cpan shell -- CPAN exploration and modules installation (v1.9456)
Enter 'h' for help.

cpan[1]> d /bioperl/
Distribution BOZO/Fry-Lib-BioPerl-0.15.tar.gz
Distribution CJFIELDS/BioPerl-1.6.1.tar.gz
Distribution CJFIELDS/BioPerl-1.6.901.tar.gz
Distribution CJFIELDS/BioPerl-Run-1.006900.tar.gz
Distribution CRAFFI/Bundle-BioPerl-2.1.8.tar.gz
5 items found


and then I choose …

cpan[2]> install C/CJ/CJFIELDS/BioPerl-1.6.901.tar.gz

From this moment on all I had to do was to follow the suggested default’s choices (and obvious customizations like the geographically based ones) and all went for the better!

installing Fedora 15 on an Asus P4B533-e supplied pc

Lately at work I had to struggle a bit with the recovery of a personal workstation. Once very powerful nowadays with the dead of some of it’s disk, the subsequent loss of any RAID functionality (investing in IDE drives doesn’t make sense), and it’s “low” 1.5GB of RAM it’s just enough for some basic uses.

Unfortunately there has been an issue with the drive that resulted in (a near) complete data loss.

It was time to reinstall it, but default procedures failed. Ubuntu, Fedora, CentOS … ALL of them gave me an issue. Then I remembered how Promise RAID chipset on main motherboard had bad comments at the time, many regarding the poor implementation of RAID drivers.

So I’ve entered the BIOS of it’s motherboard (an Asus P4B533-E model) and disabled all internal support to raid.
Then I’ve booted my Fedora 15 DVD and at the prompt I gave the

linux nodmraid

command, disable so any fake RAID in the motherboard or RAID controller BIOS so that it acts as a normal controller.
BAM! It worked!

Error booting Fedora in VirtualBox

I am in the middle of the work for a GNU/Linux keynote & hands-on demo for some colleagues.

Since I’m a loyal Fedora/CentOS user I’m installing the latest Fedora 15 on my MacBook’s VirtualBox.

Everything went ok during the installation until first reboot on which the system told me:

FATAL: INT18: BOOT FAILURE"

remaining into the error mode and forcing me to manually reboot.

If this happens to you too be sure to check if the installation media (the cd-rom or the dvd-rom) is still present in the player (!!!) and remove it.

It happears to be a know issue with VirtualBox, since a bug #2680 was opened 3 years ago and still unresolved (probably because it’s unclear if it’s VirtualBox or Fedora dvd boot system fault).
Ejecting the optical media solved my issue, cheers!