GNU/Linux

It's been a couple of days since I bought a ZTE MF667 USB 3G modem for the few days that I will be for vacation and internet access is mostly necessary. The first thing I had to do is to confirm that this modem works with Linux.

Plugging it in for the first time and network manager did nothing. The first thing to do is to search for possible solutions (using my wired connection). After a few posts, I couldn't figure out what was missing. The last post found presented the correct solution.

The news is hitting the web. Debian might be forked in case systemd is the only viable init system in the future. Pay attention to the word viable.

Αυτή τη βδομάδα, ήμουν σε ένα σεμινάριο που διοργανώνει το ΕΚΔΔΑ (Εθνικό Κέντρο Δημόσιας Διοίκησης & Αυτοδιοίκησης), ο φορέας που αναλαμβάνει τις εκπαιδεύσεις των δημοσίων υπαλλήλων. Το θέμα του σεμιναρίου ήταν «Τα λειτουργικά συστήματα Unix και Linux». Το δήλωσα εξαρχής, γιατί θεώρησα ότι θα υπάρχουν σίγουρα πράματα που θα μάθαινα, αλλά επειδή και δεδομένης της (όποιας) εμπειρίας έχω με το Linux, θα ήθελα να δω αν όντως είναι ένα σεμινάριο που θα παρακολουθήσει κάποιος για να μπορέσει να έχει μια αρχική επαφή με το Linux και να αρχίσει την ενασχόλησή του με αυτό. Στο παρόν κείμενο, θα σας μεταφέρω την τελική μου άποψη.

Today, I had to install 64-bit Debian Wheezy (7.2) on a HP ProLiant ML 350 G5 server. I downloaded the netinst iso, burnt it and booted the server. I chose the Expert install at the GRUB screen loader and after a few options, it successfully detected the two network interfaces (both from Broadcom, different models, a NetXtreme II and a Tigon3). But it displayed a message that these nics require non-free firmware files and that I had to load them if I wanted the cards to work. Puzzled. I continued the installation, but as warned, the nics would not acquire an IP address from the DHCP server.

Back to the basics, search. The solution was finally rather simple. You have two options:

• Download separately the firmware files, write them to a USB flash drive and load them during the installation.
• Download a unofficially maintained netinst image that already contains all these non-free firmware files (from http://cdimage.debian.org/cdimage/unofficial/non-free/cd-including-firmware/).

Since I had already burnt the official netinst image and I had no other empty CDs, I had to try the first option. I downloaded from http://cdimage.debian.org/cdimage/unofficial/non-free/firmware/ the tar.gz (or zip) file for Wheezy, untarred (or unzipped) the files at an empty USB flash and rebooted the server, so that the installation will start again from scratch. The installation started and at the point of the warning message about the firmware files, I inserted the USB flash. I clicked on Yes to load the firmware files from a removable location and voilà! It worked. The installation finished after a few minutes (and it was rather quick).

I suppose the second option (the unofficial iso image with the firmware files already inside) will also work fine.

Another Linux deployment worked flawlessly.

It's been a long time since I last posted something in my blog, so it's about time I did now.

It's been a while since PHP 5.4 was released. One of the features/improvements that was described in its release notes was the reduced memory usage when compared to v. 5.3. So, I thought about giving it a try and do some tests.

The test was focused only on peak memory usage when fullfilling a request. I used PHP versions 5.3.23 and 5.4.13 (the current stable ones in Gentoo). I also tested with and without the Xcache 3.0.1 accelerator.

Today is the day when both Drupal 7.0 and Linux 2.6.37 were released.

For the first, you can read about in the release announcement, while for the latter you can read about at the kernelnewbies page.

And as I would say in Greek: «Τυχαίο που βγήκαν και τα δύο μαζί; Δε νομίζω!!» 

Those of you Opera users that have problems with accents in the address and search bars (for example, I couldn't type έ or ά in Greek), in case you have compositing enabled, disable it and restart Opera. Otherwise you can start Opera like this:

opera -noargb

and the problems will go away. This has been an annoying problem for me (I don't remember which version introduced this issue, maybe 10.60) and I was looking forward for a solution. This simply does it.

It's been a while since my last benchmarks for some of the most widely used and known Linux filesystems and I think it's time to refresh them. This time, I've added ext4, which was marked stable since Linux 2.6.28 (the previous benchmarks were based on 2.6.26). Take a look at the attached file, in the first two pages, you will find information regarding my system setup, which was the basis for the new benchmarks.

Of course, any comments are always welcome. I wish you a good reading.

Update: Thanks to user Xerion at ADSLgr.com, I've attached a new PDF file, that was exported without the PDF/A-1a option checked in Openoffice.org, which had a verified bug (and fixed in version 3.2) with this option checked. This bug affected some PDF readers (like Adobe Acrobat), but not others (Evince, Okular, etc.). Thanks for the notification Xerion!

Ο Steven J. Vaughan-Nichols γράφει ένα ενδιαφέρον blog με θέμα «Five ways the Linux desktop shoots itself in the foot». Τα σημεία που θίγει είναι ενδιαφέροντα, ωστόσο εγώ θα σταθώ σε ένα, στο υπ' αριθμόν 3, με τίτλο «Too much bad techie attitude».

OK, we Linux users all know of the ext2 and ext3 filesystems. Ext2 and ext3 -the latest years- are ones of the most widely used filesystems for Linux. Ext3 was not much different from ext2, it's just a ext2 filesystem with a journal. In fact, you can mount a ext3 partition as ext2; the only difference is that you wοn't have a journal enabled.

Now the time has come and ext4 has emerged. After Linux 2.6.28 was released (remember, Linux is the kernel), ext4 was marked as stable. Ext4 is somewhat backwards compatible with ext3. You can mount an existing ext3 filesystem as ext4 and the new files will use the new ext4 features. You can also mount a ext4 partition as ext3, provided that you don't use extents, a new ext4 feature.

Anyway, what's the point to have a mixed ext3 and ext4 filesystem? This is a quick guide to convert your existing ext3 (or other FS type) partition to ext4, which I followed today.